Wind power flexible direct current grid-connected system frequency modulation control method and system

Abstract

The invention provides a wind power flexible direct current grid-connected system frequency modulation control method and system, and relates to the field of wind power flexible direct current grid-connected systems, and the method comprises the steps: obtaining a reactive current value, and dividing the reactive current value into each fan according to a preset proportion; establishing a mathematical model according to proportional control, integral control and differential control to obtain a target function, and optimizing the target function through an improved PRGO optimization algorithm to update a preset proportion to obtain a target proportion; dividing the reactive current value into each fan according to the target proportion so as to modulate the frequency of the wind power flexible direct current grid-connected system; proportional gain, differential gain and integral gain of a PID controller are optimized by adopting an improved PRGO optimization algorithm, and the obtained parameters effectively improve the frequency modulation control precision of the wind power flexible direct current grid-connected system, so that the wind power plant flexible direct current grid-connected system maintains a stable operation state; the technical problem that the frequency modulation control of the wind power flexible direct current grid-connected system cannot be realized in the prior art is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of wind power flexible direct current grid-connected systems, and in particular to a frequency modulation control method and system for wind power flexible direct current grid-connected systems. Background Art

[0002] Wind power flexible direct current grid-connected system refers to a system that connects wind power generation system to the power grid through flexible direct current transmission technology (Voltage Source Converter High Voltage Direct Current, referred to as VSC-HVDC). Through the frequency control of wind power flexible direct current grid-connected system, the system can be kept in a stable frequency state and maintain a reliable operation state.

[0003] At present, there are many studies on wind power flexible direct current grid-connected systems. One is to apply the harmonic injection information transmission method to the wind power flexible direct current grid-connected system to solve the harmonic resonance, communication delay, and submodule failure of the wind power flexible direct current grid-connected system; the other is to apply the improved V / F control strategy (i.e., voltage-frequency ratio control strategy) to the direct-drive wind power flexible direct current grid-connected system to improve the system's operating stability. The above two methods provide the necessary basis for the stable operation of the wind power flexible direct current grid-connected system, but cannot achieve the frequency modulation control of the wind power flexible direct current grid-connected system. Summary of the invention

[0004] Based on this, the purpose of the present invention is to provide a frequency regulation control method and system for a wind power flexible direct current grid-connected system, so as to solve the technical problem that the frequency regulation control of a wind power flexible direct current grid-connected system cannot be realized in the prior art.

[0005] On one hand, the present invention provides a frequency modulation control method for a wind power flexible direct current grid-connected system, which is applied to a PID controller, wherein the PID controller includes proportional control, integral control and differential control, and the method includes: Obtaining reactive current values ​​to divide the reactive current values ​​into each wind turbine according to a preset ratio; A mathematical model is established according to proportional control, integral control and differential control to obtain an objective function, and the objective function is optimized by an improved PRGO optimization algorithm to update the preset ratio to obtain a target ratio, wherein the target ratio includes a target proportional gain, a target differential gain and a target integral gain; Divide the reactive current value to each wind turbine according to the target ratio to adjust the frequency of the wind power flexible direct current grid-connected system; Among them, the improved PRGO optimization algorithm includes a fiber root growth mathematical model, and the expression of the fiber root growth mathematical model is: ; In the formula, Seed 1 represents the growth of the i-th fiber root for the t+1th time;X best It means that the best fiber root has been found so far in history; X worst It means that the worst fiber root in history has been searched so far; represents the t-th growth of the i-th fiber root; represents a fiber root randomly selected from the N fiber roots grown for the tth time; α 1 is a random number in the interval (-0.5, 1.5); or Represents a constant that changes with the number of iterations; t Indicates the current iteration number; T max Indicates the maximum number of iterations.

[0006] The above-mentioned frequency regulation control method of the wind power flexible direct current grid-connected system optimizes the proportional gain, differential gain and integral gain of the PID controller by adopting the improved PRGO optimization algorithm to obtain the target proportion, obtains the optimized PID controller parameters according to the target proportion, and improves the control accuracy of the PID controller according to the optimized PID controller parameters, so that the obtained PID controller parameters effectively improve the control accuracy of the frequency regulation of the wind power flexible direct current grid-connected system, so that the wind farm flexible direct current grid-connected system maintains a stable operating state; and solves the technical problem that the frequency regulation control of the wind power flexible direct current grid-connected system cannot be realized in the prior art.

[0007] In addition, the frequency modulation control method of the wind power flexible direct current grid-connected system according to the present invention may also have the following additional technical features: Furthermore, the improved PRGO optimization algorithm also includes a taproot growth mathematical model, and the expression of the taproot growth mathematical model is: ; In the formula, Seed 2 Indicates the nutrients absorbed by the lateral roots during the t+1th growth; Seed 3 It represents the nutrients absorbed by the taproot during the t+1th growth; is the entire soil space; u and l are the upper and lower bounds of the problem space respectively; α 3 is a random integer; for e The negation of e When taking 1, α 3 ∈(0,1); when e When 0 is taken, α 3 =1; g is a random value.

[0008] Furthermore, the improved PRGO optimization algorithm also includes a mathematical model for the growth of fibrous root plants, and the expression of the mathematical model for the growth of fibrous root plants is: ; In the formula, X c Indicates the current adventitious root Guide the rest of the rhizomes except the thick adventitious roots to diffuse and grow in the soil to absorb nutrients. 4 It represents the nutrients absorbed by the adventitious roots during the t+1th growth; α 4 Represents a random number; s is a random integer of 0 or 1 generated by the rand(0,1) function. s =1, α 4 ∈(0,1), when s =0, α 4 =0; r3 and r4 are random integers selected from the interval (1,N) and r3≠r4; λ 1 and λ 2 Both represent weights; X r3 and X r4 They represent the r3th individual and the r4th individual respectively.

[0009] Furthermore, the step of optimizing the objective function by using the improved PRGO optimization algorithm to update the preset ratio to obtain the target ratio includes: Get the current iteration number; Determine whether the current number of iterations has reached the maximum number of iterations; If not, continue iterating; If yes, stop the iteration and output the target ratio.

[0010] Another aspect of the present invention provides a frequency modulation control system for a wind power flexible direct current grid-connected system, which is applied to a PID controller, wherein the PID controller includes proportional control, integral control and differential control, and the system includes: An acquisition module, used for acquiring a reactive current value so as to divide the reactive current value into each wind turbine according to a preset ratio; An optimization module, used to establish a mathematical model according to proportional control, integral control and differential control to obtain an objective function, and optimize the objective function through an improved PRGO optimization algorithm to update the preset ratio to obtain a target ratio, wherein the target ratio includes a target proportional gain, a target differential gain and a target integral gain; Frequency regulation module, used to divide the reactive current value to each wind turbine according to the target ratio to regulate the frequency of the wind power flexible direct current grid-connected system; Among them, the improved PRGO optimization algorithm includes a fiber root growth mathematical model, and the expression of the fiber root growth mathematical model is: ; In the formula, Seed 1 represents the growth of the i-th fiber root for the t+1th time; X best It means that the best fiber root has been found so far in history; X worst It means that the worst fiber root in history has been searched so far; represents the t-th growth of the i-th fiber root; represents a fiber root randomly selected from the N fiber roots grown for the tth time; α 1 It is a random number in the interval (-0.5,1.5); or Represents a constant that changes with the number of iterations; t Indicates the current iteration number; T max Indicates the maximum number of iterations.

[0011] Another aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the frequency regulation control method for a wind power flexible direct current grid-connected system as described above.

[0012] On the other hand, the present invention also provides a data processing device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the frequency regulation control method of the wind power flexible direct current grid-connected system as described above is implemented. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a flow chart of a frequency modulation control method of a wind power flexible direct current grid-connected system in an embodiment of the present invention; Figure 2 Schematic diagram showing the comparison between the number of iterations and the fitness value of the improved PRGO optimization algorithm and the conventional PRGO optimization algorithm in the embodiment of the present invention; The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0014] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. Several embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0015] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0016] The two methods in the prior art provide the necessary basis for the stable operation of the wind power flexible direct-connected grid-connected system, but cannot realize the frequency modulation control of the wind power flexible direct-connected grid-connected system. The PID control algorithm has the characteristics of strong robustness, but has the defects of high error and poor control accuracy caused by nonlinear motion. Therefore, a frequency modulation control method for a wind power flexible direct-connected grid-connected system is urgently needed to solve the technical problem that the frequency modulation control of the wind power flexible direct-connected grid-connected system cannot be realized in the prior art. Specifically, the present application provides a frequency modulation control method and system for a wind power flexible direct-connected grid-connected system, which optimizes the proportional gain, differential gain and integral gain of the PID controller by adopting an improved PRGO optimization algorithm to obtain a target proportion, obtains the optimized PID controller parameters according to the target proportion, and improves the control accuracy of the PID controller according to the optimized PID controller parameters, so that the obtained PID controller parameters effectively improve the control accuracy of the frequency modulation of the wind power flexible direct-connected grid-connected system, thereby maintaining a stable operating state of the wind farm flexible direct-connected grid-connected system; and solves the technical problem that the frequency modulation control of the wind power flexible direct-connected grid-connected system cannot be realized in the prior art.

[0017] In order to facilitate understanding of the present invention, several embodiments of the present invention are provided below. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0018] Embodiment 1 See also Figure 1 , which shows a frequency modulation control method for a wind power flexible direct current grid-connected system in a first embodiment of the present invention, and is applied to a PID controller, wherein the PID controller includes proportional control, integral control and differential control, and the method includes steps S101 to S103: S101, obtaining reactive current values ​​to divide the reactive current values ​​into respective wind turbines according to a preset ratio.

[0019] S102. A mathematical model is established according to proportional control, integral control and differential control to obtain an objective function. The objective function is optimized by an improved PRGO optimization algorithm to update a preset ratio to obtain a target ratio, wherein the target ratio includes a target proportional gain, a target differential gain and a target integral gain.

[0020] The objective functions established include proportional control, integral control and differential control. Specifically: Proportional control. The signal output gain is adjusted through the proportional control of the PID controller. The frequency modulation control of the wind power flexible direct current grid-connected system forms a deviation lag, and the proportional control link is used to control the system frequency modulation. The larger the deviation value, the stronger the control performance of the proportional control link, the lower the system deviation, and the ideal input of the reactive current value of the wind power flexible direct current grid-connected system is completed. Specifically, the objective function of proportional control is as follows: u(τ)=K 1 ﹒ e(τ) e(τ)=r(τ)-y(τ) Where: K 1 represents the proportional gain, e(τ) and r(τ) represent the error signal and the reactive current reference signal respectively; u(τ) represents the objective function of proportional control, y(τ) represents the reactive current feedback signal; τ represents time.

[0021] Integral control. The force of the PID controller's integral control is positively correlated with the set integral size. The error between the reactive current command signal and the output signal of the wind power flexible direct current grid-connected system is eliminated by introducing the integral term. The objective function expression of the integral control is as follows: ; in, represents the objective function of integral control, K 2 and They represent the integral gain and integral time constant of the PID controller respectively; τ represents time.

[0022] Differential control. Through the differential control link of the PID controller, the dynamic adjustment of the system frequency modulation control is completed. The introduction of the differential control link improves the rapid response capability of the PID controller and makes the control performance of the PID controller more stable. The objective function expression of the differential control is as follows: ; In the formula, represents the objective function of differential control, K 3 and represents the differential gain and the differential time constant; τ represents the time.

[0023] As a specific example, in order to avoid the problem of uneven distribution of the initial population due to the random generation of the initial population of the original algorithm, this application introduces the Henon chaotic map to initialize the population to set the initial population number and the maximum number of iterations, specifically: ; in: x i,j=( ub - lb )+ lb ; x i,j =cos(π(4r x i,j (1- x i,j )+(1-r)sin(π x i,j )-0.5)),r∈[0,1]; In the formula, X represents the initial population, x i,j Representative i The individual in j The values ​​in the dimensions, where i ∈1,2,…,n; j ∈1,2,…,d; n is the population size, d is the dimension of the problem; each individual represents a set of optimal proportional gain, differential gain and integral gain parameter solutions for the PID controller. ub and lb are the upper bound and the lower bound of the problem respectively; r represents a random number between 0 and 1.

[0024] Furthermore, in order to obtain a better ratio to update the preset ratio, specifically, the step of optimizing the objective function by the improved PRGO optimization algorithm to update the preset ratio and obtain the target ratio includes: Get the current number of iterations; determine whether the current number of iterations has reached the maximum number of iterations; if it has not reached the maximum number of iterations, continue iterating; if it has reached the maximum number of iterations, stop iterating and output the target ratio.

[0025] It should be further explained that the target ratio is the best ratio within the set maximum number of iterations, so that the reactive current value can be better divided into the ratios of each wind turbine. Figure 2 As shown in FIG. 1 , from the relationship diagram between the number of iterations and the fitness value of the improved PRGO optimization algorithm and the conventional PRGO optimization algorithm, it can be seen that the improved PRGO optimization algorithm and the conventional PRGO optimization algorithm can find better individuals.

[0026] In this embodiment, the improved PRGO optimization algorithm includes a fibrous root growth mathematical model, a taproot growth mathematical model, and a fibrous root system plant growth mathematical model.

[0027] Among them, in order to avoid the problem of high convergence precision of the PRGO optimization algorithm in the early stage of iteration, as a specific example, an adaptive elite selection formula is introduced in the fiber root growth mathematical model part of the PRGO optimization algorithm to improve its convergence precision. Specifically, the expression of the improved fiber root growth mathematical model is: ; In the formula, Seed 1 Indicates the t+1th growth i fibrous roots; X best It means that the best fiber root has been found so far in history; X worst It means that the worst fiber root in history has been searched so far; represents the t-th growth of the i-th fiber root; represents a fiber root randomly selected from the N fiber roots grown for the tth time; α 1 is a random number in the interval (-0.5, 1.5); or Represents a constant that changes with the number of iterations; t Indicates the current iteration number; T max Indicates the maximum number of iterations.

[0028] Secondly, in order to avoid the problem that the PRGO optimization algorithm is prone to fall into the local optimum in the later stage of iteration, in this embodiment, an escape formula is introduced into the taproot growth mathematical model part of the PRGO optimization algorithm to help jump out of the local optimum. Specifically, the expression of the improved taproot growth mathematical model is: ; In the formula, Seed 2 Indicates the nutrients absorbed by the lateral roots during the t+1th growth; Seed 3 It represents the nutrients absorbed by the taproot during the t+1th growth; is the entire soil space, i.e., the target problem search space; u and l are the upper and lower bounds of the problem space respectively; α 3 is a random integer; for e The negation of e When taking 1, α 3 ∈(0,1); when e When 0 is taken, α 3 =1; g is a random value.

[0029] Furthermore, in order to avoid the problem of slow operation speed of the PRGO optimization algorithm, in this embodiment, an adaptive factor is introduced into the fibrous root plant growth mathematical model part of the PRGO optimization algorithm to improve the operation speed. Specifically, the expression of the improved fibrous root plant growth mathematical model is: ; In the formula, X c Indicates the current adventitious root Guide the rest of the rhizomes except the thick adventitious roots to diffuse and grow in the soil to absorb nutrients. 4 It represents the nutrients absorbed by the adventitious roots during the t+1th growth; α 4 Represents a random number; s is a random integer of 0 or 1 generated by the rand(0,1) function. s =1, α 4 ∈(0,1), when s =0, α 4 =0; r3 and r4 are random integers selected from the interval (1,N) and r3≠r4; λ 1 and λ 2 Both represent weights; X r3 and X r4 They represent the r3th individual and the r4th individual respectively.

[0030] S103, dividing the reactive current value into each wind turbine according to the target ratio to adjust the frequency of the wind power flexible direct current grid-connected system.

[0031] In summary, the frequency modulation control method of the wind power flexible direct current grid-connected system in the above-mentioned embodiment of the present invention optimizes the proportional gain, differential gain and integral gain of the PID controller by adopting the improved PRGO optimization algorithm to obtain the target proportion, obtains the optimized PID controller parameters according to the target proportion, and improves the control accuracy of the PID controller according to the optimized PID controller parameters, so that the obtained PID controller parameters effectively improve the control accuracy of the frequency modulation of the wind power flexible direct current grid-connected system, so that the wind farm flexible direct current grid-connected system maintains a stable operating state; and solves the technical problem that the frequency modulation control of the wind power flexible direct current grid-connected system cannot be realized in the prior art.

[0032] Embodiment 2 The second embodiment of the present invention provides a frequency modulation control system for a wind power flexible direct current grid-connected system, which is applied to a PID controller. The PID controller includes proportional control, integral control and differential control. The system includes: An acquisition module, used for acquiring a reactive current value so as to divide the reactive current value into each wind turbine according to a preset ratio; An optimization module, used to establish a mathematical model according to proportional control, integral control and differential control to obtain an objective function, and optimize the objective function through an improved PRGO optimization algorithm to update the preset ratio to obtain a target ratio, wherein the target ratio includes a target proportional gain, a target differential gain and a target integral gain; Frequency regulation module, used to divide the reactive current value to each wind turbine according to the target ratio to regulate the frequency of the wind power flexible direct current grid-connected system; Among them, the improved PRGO optimization algorithm includes a fiber root growth mathematical model, and the expression of the fiber root growth mathematical model is: ; In the formula, Seed 1 represents the growth of the i-th fiber root for the t+1th time; X best It means that the best fiber root has been found so far in history; X worst It means that the worst fiber root in history has been searched so far; represents the t-th growth of the i-th fiber root; represents a fiber root randomly selected from the N fiber roots grown for the tth time; α 1 It is a random number in the interval (-0.5,1.5); or Represents a constant that changes with the number of iterations; t Indicates the current iteration number; T max Indicates the maximum number of iterations.

[0033] In summary, the frequency regulation control system of the wind power flexible direct current grid-connected system in the above-mentioned embodiments of the present invention optimizes the proportional gain, differential gain and integral gain of the PID controller by adopting the improved PRGO optimization algorithm to obtain the target proportion, obtains the optimized PID controller parameters according to the target proportion, and improves the control accuracy of the PID controller according to the optimized PID controller parameters, so that the obtained PID controller parameters effectively improve the control accuracy of the frequency regulation of the wind power flexible direct current grid-connected system, thereby maintaining a stable operating state of the wind farm flexible direct current grid-connected system; and solves the technical problem that the frequency regulation control of the wind power flexible direct current grid-connected system cannot be realized in the prior art.

[0034] In addition, an embodiment of the present invention further provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the steps of the method in the above embodiment are implemented.

[0035] In addition, an embodiment of the present invention further provides a data processing device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the steps of the method in the above embodiment when executing the program.

[0036] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0037] More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering or processing in another suitable manner as necessary, and then stored in a computer memory.

[0038] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0039] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0040] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A frequency modulation control method for a wind power flexible direct current grid-connected system, characterized in that: Applied to a PID controller, the PID controller includes proportional control, integral control and differential control, the method includes: Obtaining reactive current values ​​to divide the reactive current values ​​into each wind turbine according to a preset ratio; A mathematical model is established according to proportional control, integral control and differential control to obtain an objective function, and the objective function is optimized by an improved PRGO optimization algorithm to update the preset ratio to obtain a target ratio, wherein the target ratio includes a target proportional gain, a target differential gain and a target integral gain; Divide the reactive current value to each wind turbine according to the target ratio to adjust the frequency of the wind power flexible direct current grid-connected system; Among them, the improved PRGO optimization algorithm includes a fiber root growth mathematical model, and the expression of the fiber root growth mathematical model is: ； In the formula, Seed1 represents the i-th fiber root grown at the t+1th time; X best It means that the best fiber root has been found so far in history; X worst It means that the worst fiber root in history has been searched so far; represents the t-th growth of the i-th fiber root; represents a fiber root randomly selected from the N fiber roots grown for the tth time; α 1 is a random number in the interval (-0.5, 1.5); η Represents a constant that changes with the number of iterations; t Indicates the current iteration number; T max Indicates the maximum number of iterations.

2. The frequency modulation control method of the wind power flexible direct current grid-connected system according to claim 1 is characterized in that: The improved PRGO optimization algorithm also includes a taproot growth mathematical model, the expression of which is: ； In the formula, Seed2 represents the nutrients absorbed by the lateral roots at the t+1th growth; Seed3 represents the nutrients absorbed by the main root at the t+1th growth; is the entire soil space, i.e., the target problem search space; u and l are the upper and lower bounds of the problem space respectively; α 3 is a random integer; for ε The negation of when ε When taking 1, α 3∈(0,1); when ε When 0 is taken, α 3=1; ζ is a random value.

3. The frequency modulation control method of the wind power flexible direct current grid-connected system according to claim 2 is characterized in that: The improved PRGO optimization algorithm also includes a mathematical model for the growth of fibrous root plants. The expression of the mathematical model for the growth of fibrous root plants is: ； In the formula, X c Indicates the current adventitious root It guides the nutrients absorbed by the rest of the rhizomes except the thick adventitious roots to diffuse and grow in the soil. Seed4 represents the nutrients absorbed by the adventitious roots in the t+1th growth; α 4 represents a random number; σ is a random integer of 0 or 1 generated by the rand(0,1) function. σ =1, α 4∈(0,1), when σ =0, α 4=0; r3 and r4 are random integers selected from the interval (1,N) and r3≠r4; λ1 and λ2 both represent weights; X r3 and X r4 They represent the r3th individual and the r4th individual respectively.

4. The frequency modulation control method of the wind power flexible direct current grid-connected system according to claim 1 is characterized in that: The step of optimizing the objective function by using the improved PRGO optimization algorithm to update the preset ratio to obtain the target ratio includes: Get the current iteration number; Determine whether the current number of iterations has reached the maximum number of iterations; If not, continue iterating; If yes, stop the iteration and output the target ratio.

5. A frequency modulation control system for a wind power flexible direct current grid-connected system, characterized in that: Applied to a PID controller, the PID controller includes proportional control, integral control and differential control, and the system includes: An acquisition module, used for acquiring a reactive current value so as to divide the reactive current value into each wind turbine according to a preset ratio; An optimization module, used to establish a mathematical model according to proportional control, integral control and differential control to obtain an objective function, and optimize the objective function through an improved PRGO optimization algorithm to update the preset ratio to obtain a target ratio, wherein the target ratio includes a target proportional gain, a target differential gain and a target integral gain; Frequency regulation module, used to divide the reactive current value to each wind turbine according to the target ratio to regulate the frequency of the wind power flexible direct current grid-connected system; Among them, the improved PRGO optimization algorithm includes a fiber root growth mathematical model, and the expression of the fiber root growth mathematical model is: ； In the formula, Seed1 represents the i-th fiber root grown at the t+1th time; X best It means that the best fiber root has been found so far in history; X worst It means that the worst fiber root in history has been searched so far; represents the t-th growth of the i-th fiber root; represents a fiber root randomly selected from the N fiber roots grown for the tth time; α 1 is a random number in the interval (-0.5, 1.5); η Represents a constant that changes with the number of iterations; t Indicates the current iteration number; T max Indicates the maximum number of iterations.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the frequency regulation control method of a wind power flexible direct current grid-connected system as described in any one of claims 1 to 4 is implemented.

7. A data processing device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the frequency regulation control method of the wind power flexible direct current grid-connected system as described in any one of claims 1 to 4 is implemented.

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