Method and system for controlling transient voltage of grid following-grid construction hybrid wind power plant

Abstract

The invention discloses a transient voltage control method and a transient voltage control system for a network following-construction hybrid wind power plant. The method comprises the following steps: 1) acquiring wind turbine generator parameters and wind turbine generator demand parameters; 2) based on the wind turbine generator parameters and the wind turbine generator demand parameters, establishing a control parameter-output frequency linearization model and a control parameter-reactive power linearization model of the network construction type wind turbine generator; 3) constructing a hybrid wind power plant double-model transient voltage controller based on the linearized model; as for the grid-forming type wind turbine generator set, the output frequency fluctuation of the grid-forming type wind turbine generator set during the transient voltage period is restrained by optimizing control parameters; for a grid-forming type wind turbine generator and a grid-following type wind turbine generator, the active power, the reactive power and the flux weakening current are optimized to reduce the terminal voltage deviation of the wind turbine generators, and meanwhile the kinetic energy storage capacity is maximized. Node voltage fluctuation can be effectively restrained, the kinetic energy storage capacity of the wind turbine generator is maximized, and the transient voltage supporting capacity of the hybrid wind power plant is enhanced.

Description

Technical Field

[0001] The present invention mainly relates to the technical field of wind power generation, and particularly relates to a transient voltage control method and system for a grid-following and grid-forming hybrid wind farm. Background Art

[0002] The randomness and volatility of wind resources pose great challenges to the voltage and frequency stability control of wind turbines and wind farms. Traditional grid-forming wind turbines lack the ability of active voltage and frequency support. With the continuous increase of the wind power grid connection capacity, the stability of the power system is at risk. Especially after a transient fault of the grid voltage, the voltage fluctuation at the grid connection point will cause the wind turbines to trip, thus threatening the operation of large-scale wind turbines.

[0003] Grid-forming wind turbines can achieve active voltage and frequency support. However, due to the characteristic of power lag in virtual synchronous control, grid-forming wind turbines face more serious voltage and frequency fluctuations under transient voltage fluctuations. Therefore, it is urgent to study how to achieve the optimal transient voltage control of a hybrid wind farm according to the transient voltage response differences between grid-forming and grid-following wind turbines. Summary of the Invention

[0004] Aiming at the technical problems existing in the prior art, the present invention provides a transient voltage control method and system for a grid-following and grid-forming hybrid wind farm, which can effectively suppress the output frequency fluctuation of grid-forming wind turbines and the node voltage fluctuation of the hybrid wind farm, and maximize the kinetic energy storage capacity of the wind turbines, and enhance the transient voltage support ability of the hybrid wind farm.

[0005] To solve the above technical problems, the technical solution proposed by the present invention is as follows: A transient voltage control method for a grid-following and grid-forming hybrid wind farm, comprising the steps of: 1) Obtain the wind turbine parameters and the wind turbine demand parameters; 2) Based on the wind turbine parameters and the wind turbine demand parameters, establish a linearized model of the control parameters-output frequency and a linearized model of the control parameters-reactive power for the grid-forming wind turbines; the control parameters include virtual damping, virtual inertia, and voltage integral coefficient; 3) Based on the linearized model of the control parameters-output frequency and the linearized model of the control parameters-reactive power, construct a dual-model transient voltage controller for the hybrid wind farm; for the grid-forming wind turbines, suppress the output frequency fluctuation of the grid-forming wind turbines during transient voltage and improve the reactive power response rate by optimizing the virtual damping, virtual inertia, and voltage integral coefficient; For both grid-forming and grid-following wind turbines, reduce the terminal voltage deviation of the wind turbines by optimizing the active power, reactive power, and field weakening current, and at the same time maximize the kinetic energy storage capacity to improve the transient voltage support ability of the wind turbines.

[0006] Preferably, in step 1), the wind turbine parameters include virtual damping D、 virtual inertia J e 、 voltage integral coefficient k e 、 rotor speed ω r 、 generator resistance R s and inductance L s , DC bus voltage V dc , active power P W , reactive power Q W and field weakening current i sd ; the wind turbine demand parameters include wind speed v , node voltage V W , wind farm line resistance R g and inductance L g .

[0007] Preferably, in step 2), the control parameter-output frequency linearization model is: ; where , , , , ; where the control parameter-reactive power linearization model is: ; where , , ; In the formula, is the grid-connected wind turbine grid-side converter voltage, is the grid-connected wind turbine grid-side converter filter line voltage, is the grid-connected wind turbine grid-side converter output power angle, D is the grid-connected wind turbine virtual damping coefficient, is the grid-connected wind turbine virtual inertia coefficient, is the grid-connected wind turbine voltage integral coefficient, is the grid-connected wind turbine output angular frequency, It is the filter inductor of the grid-forming wind turbine generator set, and are the active power and reactive power output of the grid-forming wind turbine generator set; The superscript ref represents the reference quantity, and the subscript 0 represents the initial quantity, represents the increment.

[0008] Preferably, for the grid-forming wind turbine generator set, the specific process of suppressing the output frequency fluctuation of the grid-forming wind turbine generator set during the transient voltage and improving the reactive power response rate by optimizing the virtual damping, virtual inertia, and voltage integral coefficient is as follows: Establish a grid-forming virtual synchronous control state space model, which includes two control objectives, namely the output frequency and the reactive power output; Based on the dual-model transient voltage controller of the hybrid wind farm, make full use of the kinetic energy storage capacity of the wind turbine generator set, specifically: ; ; wherein, N p is the control step size, N WM is the number of grid-forming wind turbine generator sets, is the angular frequency optimization parameter, is the angular frequency of the i th wind turbine generator set, is the angular frequency reference value; Based on the dual-model transient voltage controller of the hybrid wind farm, adaptively adjust the maximum kinetic energy storage boundary to reduce the system frequency deviation, specifically: ; wherein, is the reactive power of the i th wind turbine generator set, is the reactive power reference value of the i th wind turbine generator set, is the reactive power optimization parameter.

[0009] Preferably, in step 3), the specific process of optimizing the active power is as follows: The control objective of active power optimization is to improve the transient voltage support ability of the hybrid wind farm during the transient voltage, specifically: ; ; ; where is the active power reference value of the i th wind turbine generator set,N W represents the total number of wind turbines in the hybrid wind farm; is the active power reference value of the i th wind turbine under the MPPT mode, is the active power optimization parameter of the i th wind turbine, is the low voltage ride through optimization parameter of the i th wind turbine, is the high voltage ride through optimization parameter of the i th wind turbine, is the terminal voltage of the i th wind turbine.

[0010] Preferably, in step 3), the specific process of optimizing reactive power is as follows: The control objective of reactive power optimization is to reduce the terminal voltage deviation of the wind turbine, specifically:

[0011] where is the terminal voltage of the wind turbine, is the node voltage reference value of the hybrid wind farm, is the voltage optimization parameter; Based on the gradient projection method, the reactive power optimization iteration process of the wind turbine is:

[0012] where , is the voltage optimization parameter, is the reactive power reference value of the wind turbine at the k th iteration, is the reactive power reference value of the wind turbine at the k+1 th iteration, is the projection function, is the voltage gradient function.

[0013] Preferably, in step 3), the process of maximizing the kinetic energy storage capacity is as follows: Define kinetic energy storage parameters to quantify the maximum kinetic energy storage capacity of the wind turbine; Establish a state space model of the maximum kinetic energy storage of the grid-forming - grid-following wind turbine; Set the control objective of the kinetic energy storage parameter and the maximum kinetic energy storage control constraint conditions; Based on the control objective of the kinetic energy storage parameter and the maximum kinetic energy storage control constraint conditions, solve the state space model of the maximum kinetic energy storage of the grid-forming - grid-following wind turbine to obtain the maximized kinetic energy storage capacity.

[0014] Preferably, define the kinetic energy storage parameter To quantify the maximum kinetic energy storage capacity of a wind turbine, specifically: ; where is the rotor speed of the wind turbine, is the maximum limit of the rotor speed of the wind turbine; The kinetic energy storage parameter of the wind turbine is linearized as:

[0015] , ; ; ; In the formula, , are the sensitivity coefficients of the maximum rotor speed to the d-axis and q-axis currents of the wind turbine converter respectively, i sd and i sq are the d-axis and q-axis currents of the machine-side converter, n p is the number of rotor pole pairs, is the output electromagnetic power of the wind turbine, ψ is the magnetic flux; the subscript 0 represents the initial quantity, and the subscript max represents the maximum value, represents the increment.

[0016] Preferably, the maximum kinetic energy storage state-space model of the grid-forming and grid-following wind turbine is: ; where the state variable , the input variable , and the output variable ; , , ; , ; , , , ; In the formula, , and are the control time constants of the wind turbine, P m and P W are the mechanical power and electromagnetic power of the wind turbine,J is the moment of inertia of the synchronous generator; the superscript ref represents the reference quantity.

[0017] The present invention also discloses a grid-following and grid-forming hybrid wind farm transient voltage control system, including a memory and a processor connected to each other. A computer program is stored on the memory, and when the computer program is run by the processor, it executes the steps of the method described above.

[0018] Compared with the prior art, the advantages of the present invention are as follows: For the grid-forming wind turbines in the grid-following and grid-forming hybrid wind farm transient voltage control method of the present invention, by optimizing the virtual synchronous control parameters (virtual damping, virtual inertia, voltage integral coefficient), the output frequency fluctuation is reduced and the reactive power response rate is improved; for the grid-forming and grid-following wind turbines, by optimizing the power output and the field weakening current, the node voltage fluctuation of the wind farm is reduced by maximizing the kinetic energy storage capacity, and the transient voltage support capacity of the hybrid wind farm is enhanced. The present invention can effectively suppress the output frequency of the grid-forming wind turbines and the node voltage fluctuation of the hybrid wind farm, and maximize the kinetic energy storage capacity of the wind turbines, enhancing the transient voltage support capacity of the hybrid wind farm. Brief Description of the Drawings

[0019] Figure 1 is a flow chart of the grid-following and grid-forming hybrid wind farm transient voltage control method of the present invention.

[0020] Figure 2 is a simulation diagram of the output frequency of the grid-forming wind turbines under different control methods in the present invention.

[0021] Figure 3 is a simulation diagram of the node voltage of the hybrid wind farm under different control methods in the present invention.

[0022] Figure 4 is a simulation diagram of the active power of the wind turbines under different control methods in the present invention.

[0023] Figure 5 is a simulation diagram of the reactive power of the wind turbines under different control methods in the present invention.

[0024] Figure 6 is a simulation diagram of the kinetic energy storage coefficient of the wind turbines under different control methods in the present invention. Detailed Embodiments

[0025] The present invention will be further described below in conjunction with the drawings of the specification and specific embodiments.

[0026] As Figure 1 shown, the grid-following and grid-forming hybrid wind farm transient voltage control method of the embodiment of the present invention includes the steps: 1) Obtain the wind turbine parameters and the wind turbine demand parameters; Specifically, the wind turbine parameters include virtual damping D、 virtual inertia J e 、 voltage integral coefficient k e 、 rotor speed ω r 、 generator resistance R s and inductance L s , DC bus voltage V dc , active power P W , reactive power Q W , field weakening current i sd ; The wind turbine demand parameters include wind speed v , wind farm line resistance R g and inductance L g , node voltage V W ; 2) Based on the wind turbine parameters and the wind turbine demand parameters, according to the power angle loop and voltage loop control method of the grid-forming wind turbine, and by performing a Taylor expansion near the operating point, establish a linearized model of control parameters - output frequency and a linearized model of control parameters - reactive power for the grid-forming wind turbine; the control parameters include virtual damping, virtual inertia, and voltage integral coefficient; there is a relationship between the control parameters and the output frequency in the linearized model of control parameters - output frequency, and there is a relationship between the control parameters and the reactive power in the linearized model of control parameters - reactive power; 3) Based on the linearized model of control parameters - output frequency and the linearized model of control parameters - reactive power, establish a hybrid wind farm dual-model transient voltage controller; for the grid-forming wind turbine, suppress the output frequency fluctuation of the grid-forming wind turbine during the transient voltage period and improve the reactive power response rate by optimizing virtual damping, virtual inertia, and voltage integral coefficient; For the grid-forming wind turbine and the grid-following wind turbine, reduce the terminal voltage deviation of the wind turbine by optimizing the active power, reactive power, and field weakening current, and at the same time maximize the kinetic energy storage capacity to improve the transient voltage support ability of the wind turbine.

[0027] In a specific embodiment, in step 2), the linearized model of control parameters - output frequency is: ; Among them , , , , ; Among them, the control parameter - reactive power linearization model is: ; Among them , , ; In the formula, is the grid-connected converter voltage on the grid side of the grid-forming wind turbine generator set, is the filter line voltage of the grid-connected converter on the grid side of the grid-forming wind turbine generator set, is the output power angle of the grid-connected converter on the grid side of the grid-forming wind turbine generator set, D is the virtual damping coefficient of the grid-forming wind turbine generator set, is the virtual inertia coefficient of the grid-forming wind turbine generator set, is the voltage integral coefficient of the grid-forming wind turbine generator set, is the output angular frequency of the grid-forming wind turbine generator set, is the filter inductor of the grid-forming wind turbine generator set, and are the output active power and reactive power of the grid-forming wind turbine generator set; the superscript ref represents the reference quantity, and the subscript 0 represents the initial quantity, represents the increment, and the subscript max represents the maximum value.

[0028] In a specific embodiment, in step 3), for the grid-forming wind turbine generator set, the specific process of suppressing the output frequency fluctuation of the grid-forming wind turbine generator set during the transient voltage and improving the reactive power response rate by optimizing the virtual damping, virtual inertia, and voltage integral coefficients is as follows: Establish a grid-forming virtual synchronous control state space model (including two control objectives, namely output frequency and reactive power output):

[0029] Among them, the state variable , is the first derivative of the state variable ; the input variable , the output variable ; , , ; ; , , ; In the formula, , and are the control time constants of the virtual damping, virtual inertia, and voltage integral coefficient of the network-forming wind turbine generator.

[0030] The first objective function of the dual-model transient voltage controller for a hybrid wind farm is to make full use of the kinetic energy storage capacity of the wind turbine generator, specifically: ; ; wherein, k represents the k th step of control, N p is the total control step length, N WM is the number of network-forming wind turbine generators, is the angular frequency optimization parameter, is the i th angular frequency of the wind turbine generator, is the angular frequency reference value; The second objective function is to adaptively adjust the maximum kinetic energy storage boundary to reduce the system frequency deviation, specifically:

[0031] wherein, is the reactive power of the i th wind turbine generator, is the reactive power reference value of the i th wind turbine generator, is the reactive power optimization parameter.

[0032] In a specific embodiment, in step 3), the output power of the network-forming and network-following wind turbine generator is optimized to improve the reactive power support ability, and at the same time, the kinetic energy storage ability is maximized to improve the transient voltage support ability of the wind turbine generator, specifically: Active power control of the network-forming and network-following wind turbine generator: The active power optimization control target is to improve the transient voltage support ability of the hybrid wind farm during the transient voltage, specifically: ;

[0033] ; wherein is thei Active power reference value of typhoon wind turbine N W Indicates the total number of wind turbines in the hybrid wind farm Is the i Active power reference value of the typhoon wind turbine under the MPPT mode Is the i Active power optimization parameter of the typhoon wind turbine Is the i Low voltage ride-through optimization parameter of the typhoon wind turbine Is the i High voltage ride-through optimization parameter of the typhoon wind turbine Is the i Terminal voltage of the typhoon wind turbine

[0034] Grid-forming - grid-following wind turbine reactive power control: The reactive power optimization control objective is to reduce the terminal voltage deviation of the wind turbine, specifically:

[0035] Where Is the reference value of the node voltage of the hybrid wind farm Is the voltage optimization parameter

[0036] Based on the gradient projection method, the reactive power optimization iteration process of the wind turbine is:

[0037] Where , Is the voltage optimization parameter Is the reactive power reference value of the wind turbine at the k th iteration Is the reactive power reference value of the wind turbine at the k+1 th iteration Is the projection function Is the voltage gradient function

[0038] Grid-forming - grid-following wind turbine maximum kinetic energy storage control: Kinetic energy storage parameter Is defined to quantify the maximum kinetic energy storage capacity of the wind turbine, specifically: ; Where Is the rotor speed of the wind turbine Is the maximum limit of the rotor speed of the wind turbine

[0039] The kinetic energy storage parameter of the wind turbine can be linearized as:

[0040] , ; ; ; In the formula, and are respectively the sensitivity coefficients of the maximum rotor speed to the d-axis and q-axis currents of the wind turbine converter, i sd and i sq are the d-axis and q-axis currents of the machine-side converter, n p is the number of rotor pole pairs, is the output electromagnetic power of the wind turbine, ψ is the magnetic flux.

[0041] Establish the maximum kinetic energy storage state-space model of the grid-forming and grid-following wind turbine:

[0042] Among them, the state variable is , the input variable is , and the output variable is ; , , ; , ; , , , ; In the formula, and and are the control time constants of the wind turbine, P m and P W are the mechanical power and electromagnetic power of the wind turbine, J is the moment of inertia of the synchronous generator.

[0043] The control objective of the kinetic energy storage parameter is:

[0044] Among them, is the optimized parameter of the kinetic energy storage.

[0045] The control constraint of the maximum kinetic energy storage is: ; Among them, is thei Weak magnetic current reference value of typhoon wind turbine Is the maximum current limit of the machine-side converter of the wind turbine For the i Axis current value of the machine-side converter of typhoon wind turbine q

[0046] The transient voltage control method of the grid-following and grid-forming hybrid wind farm of the present invention, for the grid-forming wind turbines, reduces the output frequency fluctuation and improves the reactive power response rate by optimizing the virtual synchronous control parameters (virtual damping, virtual inertia, voltage integral coefficient); for the grid-forming and grid-following wind turbines, by optimizing the power output and weak magnetic current, the voltage fluctuation at the wind farm nodes is reduced by maximizing the kinetic energy storage capacity, and the transient voltage support capacity of the hybrid wind farm is enhanced. The present invention can effectively suppress the output frequency of the grid-forming wind turbines and the voltage fluctuation at the nodes of the hybrid wind farm, and maximize the kinetic energy storage capacity of the wind turbines to enhance the transient voltage support capacity of the hybrid wind farm.

[0047] As Figures 2 - 6 shown, the transient voltage control method of the grid-following and grid-forming hybrid wind farm of the present invention is simulated and verified, specifically: Figure 2 Is the output frequency simulation diagram of the grid-forming wind turbines under different control methods during transient voltage. Compared with the existing kinetic energy storage, the control method of the present invention effectively reduces the output frequency fluctuation of the grid-forming wind turbines by optimizing the virtual synchronous control parameters.

[0048] Figure 3 Is the terminal voltage simulation diagram of the wind turbines under different control methods during transient voltage. Compared with the existing model predictive control and droop control methods, the control method of the present invention further reduces the terminal voltage deviation by optimizing the active power and reactive power of the wind turbines.

[0049] Figures 4 - 5 Is the active power and reactive power output simulation diagram of the wind turbines under different control methods during transient voltage. Compared with the existing model predictive control and droop control methods, the proposed control method of the present invention reduces the voltage fluctuation at the nodes of the hybrid wind farm by optimizing the active power and reactive power, and enhances the transient voltage support capacity of the hybrid wind farm.

[0050] Figure 6 Is the kinetic energy storage coefficient simulation diagram of the wind turbines under different control methods during transient voltage. Compared with the existing model predictive control and droop control methods, the proposed control method of the present invention makes full use of the kinetic energy storage capacity by optimizing the active power and weak magnetic current, and reduces the wind energy loss.

[0051] ​An embodiment of the present invention further discloses a transient voltage control system for a network-following and network-forming hybrid wind farm, which includes a memory and a processor connected to each other. A computer program is stored on the memory, and when the computer program is run by the processor, it executes the steps of the method described above. The control system of the present invention corresponds to the above control method and also has the advantages described in the above control method.

[0052] To implement all or part of the processes in the method of the above embodiment of the present invention, it can also be completed by hardware related to computer program instructions. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, it can implement the steps of the above method embodiment. Among them, the computer program includes computer program code, and the computer program code can be in the form of source code, object code, executable file or some intermediate form, etc. The computer-readable storage medium includes: any entity or device capable of carrying computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electrical carrier signal, telecommunication signal, and software distribution medium, etc. The memory is used to store computer programs and / or modules. The processor realizes various functions by running or executing the computer programs and / or modules stored in the memory and calling the data stored in the memory. The memory can include high-speed random access memory, and can also include non-volatile memory, such as hard disk, memory, plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, at least one magnetic disk storage device, flash device, or other volatile solid-state storage devices, etc.

[0053] The above is only the preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions falling within the idea of the present invention belong to the protection scope of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements should be regarded as within the protection scope of the present invention.

Claims

1. A method for controlling transient voltage in a hybrid wind farm with a grid-connected structure, characterized in that: Includes steps: 1) Obtain wind turbine parameters and wind turbine demand parameters; 2) Based on the wind turbine parameters and wind turbine demand parameters, establish the control parameter-output frequency linearization model and control parameter-reactive power linearization model of the grid-type wind turbine; the control parameters include virtual damping, virtual inertia and voltage integral coefficient; 3) Based on the control parameter-output frequency linearization model and the control parameter-reactive power linearization model, a hybrid wind farm dual-model transient voltage controller is constructed; for grid-type wind turbines, the output frequency fluctuation of grid-type wind turbines during transient voltage is suppressed and the reactive power response rate is improved by optimizing virtual damping, virtual inertia and voltage integral coefficient; For grid-connected wind turbines and grid-following wind turbines, the voltage deviation at the wind turbine terminal is reduced by optimizing active power, reactive power and weak magnetic current, while the kinetic energy storage capacity is maximized to improve the transient voltage support capacity of the wind turbine.

2. The transient voltage control method of a grid-following-grid-building hybrid wind farm according to claim 1 is characterized in that: In step 1), the wind turbine parameters include virtual damping D、 Virtual inertia J e 、 Voltage integral coefficient k e 、 Rotor speed ω r 、 Generator resistance R s With inductor L s , DC bus voltage V dc , Active Power P W , reactive power Q W and field weakening current i sd ; Wind turbine demand parameters include wind speed v , node voltage V W , Wind farm line resistance R g and inductance L g .

3. The transient voltage control method of a grid-following-grid-building hybrid wind farm according to claim 2 is characterized in that: In step 2), the control parameter-output frequency linearization model is: ； in , , , , ; The control parameter-reactive power linearization model is: ； in , , ; In the formula, is the grid-side converter voltage of the grid-type wind turbine, To filter the line voltage of the grid-side converter of the grid-type wind turbine, is the output power angle of the grid-side converter of the grid-type wind turbine, D is the virtual damping coefficient of the grid-type wind turbine, is the virtual inertia coefficient of the grid-type wind turbine, is the voltage integral coefficient of the grid-connected wind turbine generator set, is the output angular frequency of the grid-type wind turbines, It is the inductor of the grid-type wind turbine filter. and It is the active power and reactive power output by the grid-connected wind turbines; Superscript ref Indicates reference quantity, subscript 0 represents the initial amount, Indicates increment.

4. The transient voltage control method of a grid-following-grid-building hybrid wind farm according to claim 3 is characterized in that: For grid-type wind turbines, the specific process of suppressing the output frequency fluctuation of grid-type wind turbines during transient voltage and improving the reactive power response rate by optimizing virtual damping, virtual inertia and voltage integral coefficient is as follows: A grid-based virtual synchronous control state space model is established, which includes two control targets: output frequency and reactive power output. Based on the hybrid wind farm dual-model transient voltage controller, the kinetic energy storage capacity of wind turbines is fully utilized, specifically: ； ； in, N p To control the step size, N WM is the number of grid-type wind turbines, Optimize the parameters for angular frequency, For the i Typhoon turbine angular frequency, is the angular frequency reference value; Based on the hybrid wind farm dual-model transient voltage controller, the maximum kinetic energy storage boundary is adaptively adjusted to reduce the system frequency deviation, specifically: ； in, For the i Reactive power of typhoon generators, For the i Reactive power reference value of typhoon generator set, Optimize parameters for reactive power.

5. The method for controlling transient voltage of a hybrid wind farm with a grid-connected structure according to any one of claims 1 to 4, characterized in that: In step 3), the specific process of optimizing active power is: The active power optimization control objective is to improve the transient voltage support capability of the hybrid wind farm during transient voltage periods, specifically: ； ； ； in For the i Reference value of active power of typhoon generator sets, N W Indicates the total number of wind turbines in the hybrid wind farm; For the i Active power reference value of typhoon generator set in MPPT mode, For the i Typhoon turbine active power optimization parameters, For the i Optimized parameters of low voltage ride-through for typhoon generators, For the i Optimized parameters of high voltage ride-through for typhoon turbines, For the i Typhoon turbine terminal voltage.

6. The transient voltage control method of a grid-following-grid-building hybrid wind farm according to any one of claims 1 to 4, characterized in that: In step 3), the specific process of optimizing reactive power is: The goal of reactive power optimization control is to reduce the voltage deviation at the wind turbine terminal, specifically: in is the wind turbine terminal voltage, is the node voltage reference value of the hybrid wind farm, Optimize parameters for voltage; Based on the gradient projection method, the iterative process of wind turbine reactive power optimization is: in , is the voltage optimization parameter, For iteration k Secondary wind turbine reactive power reference value, For iteration k+1 Secondary wind turbine reactive power reference value, is the projection function, is a function of the voltage gradient.

7. The method for controlling transient voltage of a hybrid wind farm with a grid-connected structure according to any one of claims 1 to 4, characterized in that: In step 3), the process of maximizing kinetic energy storage capacity is: Define kinetic energy storage parameters to quantify the maximum kinetic energy storage capacity of wind turbines; Establish the state space model of maximum kinetic energy storage of wind turbines in the grid-connected and grid-following mode; Setting kinetic energy storage parameter control targets and maximum kinetic energy storage control constraints; Based on the kinetic energy storage parameter control objectives and the maximum kinetic energy storage control constraints, the maximum kinetic energy storage state space model of the grid-connected and grid-following wind turbines is solved to obtain the maximized kinetic energy storage capacity.

8. The transient voltage control method of a grid-following-grid-building hybrid wind farm according to claim 7 is characterized in that: Defining Kinetic Energy Storage Parameters To quantify the maximum kinetic energy storage capacity of a wind turbine, specifically: ； in is the wind turbine rotor speed, The maximum limit of wind turbine rotor speed; The kinetic energy storage parameters of the wind turbine are linearized as follows: ， ； ； ； In the formula, , are the sensitivity coefficients of the maximum rotor speed to the d-axis and q-axis currents of the wind turbine converter, i sd and i sq is the d-axis and q-axis current of the machine-side converter, n p is the number of rotor pole pairs, Output electromagnetic power for wind turbines. ψ is the magnetic link; 0 Indicates the initial amount, subscript max Indicates the maximum value, Indicates increment.

9. The transient voltage control method of a grid-following-grid-building hybrid wind farm according to claim 8 is characterized in that: The state space model of the maximum kinetic energy storage of the grid-connected wind turbine is: ； The state variables , input variable , output variable ; ， ， ； ， ； ， ， ， ； In the formula, , and is the wind turbine control time constant, P m and P W is the mechanical power and electromagnetic power of the wind turbine, J is the moment of inertia of the synchronous generator; ref Indicates a reference quantity.

10. A grid-connected and grid-building hybrid wind farm transient voltage control system, comprising a memory and a processor connected to each other, wherein a computer program is stored in the memory, characterized in that: When the computer program is executed by a processor, the computer program performs the steps of the method according to any one of claims 1 to 9.

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