CN117332602B - A method and device for simulating primary frequency modulation of a wind turbine generator - Google Patents

Abstract

The present application provides a method and device for simulating primary frequency modulation of a wind turbine, wherein the method comprises: obtaining a reference output power variation for controlling the wind turbine to perform primary frequency modulation; constructing a preset state space expression corresponding to the preset wind speed interval based on a relationship between the electromagnetic torque of the wind turbine and the electromagnetic torque variable in a preset wind speed interval, in combination with a double-mass model and a variable pitch model of the wind turbine, wherein the preset state space expression is used to characterize the relationship between the preset state variable of the wind turbine and the reference output power variation in the preset wind speed interval; determining a target state space expression corresponding to the target wind speed interval based on a target wind speed interval to which the current wind speed belongs; substituting the reference output power variation into the target state space expression, and calculating the preset state variable of the primary frequency modulation, so as to perform primary frequency modulation simulation on the wind turbine.

Description

A method and device for simulating primary frequency modulation of a wind turbine generator

Technical Field

The present application relates to the technical field of wind power generation, and in particular to a method and device for simulating primary frequency modulation of a wind turbine.

Background Art

For variable-speed wind turbines, the current modeling methods for the primary frequency modulation response of wind turbines include two categories: "black box model" driven by input-output data and "white box modeling" based on mechanism analysis. Among them, the black box model relies on the specified input and output characteristics and requires a large amount of input and output data. It can achieve high-precision characterization of the dynamic characteristics of the unit structure through machine learning algorithms. However, the physical meaning of the parameters of this method is poorly interpretable and has a strong dependence on the accuracy and quantity of input data. Although the representative simulation software of wind turbines such as GH Bladed and FAST in the white box model contains high-fidelity models of high-order nonlinear dynamics, their models are too complex to be suitable for controller design. Most white box mechanism models of the primary frequency modulation response of wind turbines based on small signal derivation have strict requirements on the input signal of the frequency modulation command, and are not suitable for situations where the mechanism parameters change during actual complex working conditions.

Summary of the invention

In view of this, the purpose of the present application is to at least provide a method and device for simulating the primary frequency modulation of a wind turbine, by converting the power change during the primary frequency modulation of the wind turbine into a state space expression corresponding to the preset state parameters in different wind speed ranges, so as to convert the power change into a linear expression related to the preset state parameters, so that when the reference output power change of the output power of the generator is received, a preset state parameter is calculated according to the state space expression corresponding to the wind speed range to which the current wind speed belongs, so that the wind turbine is simulated to operate according to the calculated preset state parameters to simulate the primary frequency modulation of the wind turbine, thereby solving the technical problems in the prior art that a large amount of data is required for primary frequency modulation simulation and the constructed model is too complicated, and the technical effect of improving the efficiency of primary frequency modulation simulation of the wind turbine is achieved.

This application mainly includes the following aspects:

In a first aspect, an embodiment of the present application provides a method for simulating primary frequency regulation of a wind turbine, the method comprising: obtaining a reference output power change for controlling the wind turbine to perform primary frequency regulation; constructing a preset state space expression corresponding to the preset wind speed range based on a relationship between the electromagnetic torque of the wind turbine and the electromagnetic torque variable in a preset wind speed range, in combination with a double-mass model and a variable pitch model of the wind turbine, the preset state space expression being used to characterize the relationship between the preset state variables of the wind turbine and the reference output power change in the preset wind speed range; determining a target state space expression corresponding to the target wind speed range based on the target wind speed range to which the current wind speed belongs; substituting the reference output power change into the target state space expression, and calculating the preset state variables of the primary frequency regulation to perform primary frequency regulation simulation on the wind turbine.

Optionally, the preset wind speed interval includes a first preset interval and a second preset interval, the upper limit value of the first preset interval is equal to the lower limit value of the second preset interval, the preset state space expression includes a first state space expression corresponding to the first preset interval and a second state space expression corresponding to the second preset interval, the target wind speed interval is one of the first preset interval and the second preset interval, and the target state space expression is one of the first state space expression and the second state space expression, wherein, when the preset wind speed interval is the first preset interval, the first state space expression is used to characterize the relationship between the preset state variables of the wind turbine and the reference output power change when only the electromagnetic torque of the wind turbine is changed; when the preset wind speed interval is the second preset interval, the second state space expression is used to characterize the relationship between the preset state variables of the wind turbine and the reference output power change when only the pitch angle of the wind turbine is changed.

Optionally, a preset state space expression corresponding to the preset wind speed interval is constructed in the following manner: based on the aerodynamic torque formula of the wind turbine blade, a linear formula related to the aerodynamic torque and multiple preset parameters is constructed, each preset parameter is a parameter in the aerodynamic torque formula of the wind turbine blade and a parameter that changes during the power generation process; based on the relationship between the electromagnetic torque of the wind turbine and the reference electromagnetic torque, in combination with the linear formula, the dual-mass model and the variable pitch model of the wind turbine, a standard state space expression of the wind turbine is constructed, the standard state space expression is used to characterize the relationship between the preset state parameters of the wind turbine and the changes corresponding to the multiple preset parameters, as well as the relationship between the output power of the wind turbine and the initial output power. The preset state parameter is a parameter that changes during the power generation process; wherein, when only the electromagnetic torque of the wind turbine is changed, the first state space expression is constructed by the relationship between the electromagnetic torque and the reference output power change, the standard state space expression and the first-order inertia link expression of the pitch angle in the variable pitch model when the pitch angle reference value is zero; when only the pitch angle of the wind turbine is changed, the second state space expression is constructed by the relationship between the pitch angle derivative and the reference output power change, the standard state space expression, the relationship between the output power and the initial output power and the relationship between the electromagnetic torque and the reference electromagnetic torque when the electromagnetic torque variable is zero.

Optionally, a linear formula relating the pneumatic torque to a plurality of preset parameters is constructed by the following formula:

T _r = a×ω _r + b×β+c×V+d

Among them, P _r is the aerodynamic power of the wind turbine, ρ is the air density, R is the radius of the wind turbine rotor, V is the wind speed, C _P (λ, β) is the wind energy utilization coefficient, λ is the tip speed ratio of the wind turbine rotor, β is the pitch angle, ω _r is the wind turbine rotor speed, _Tr is the aerodynamic torque of the wind turbine, ω _r , β and V are all preset parameters, a is the coefficient corresponding to ω _r , b is the coefficient corresponding to β, c is the coefficient corresponding to V, and d is the constant term of the linear formula.

Optionally, the relationship between the electromagnetic torque of the wind turbine and the reference electromagnetic torque is:

Where, _Tg is the electromagnetic torque of the generator rotor; is the derivative of the electromagnetic torque of the generator rotor; τ _g is the generator constant; T _ref is the reference electromagnetic torque of the wind generator;

The dual mass model is represented by the following formula:

Wherein, _Jr is the moment of inertia of the fan rotor of the wind turbine; _Jg is the moment of inertia of the generator rotor of the wind turbine; _Tshaft is the equivalent intermediate shaft torque between _the fan rotor and the generator rotor; _Tr is the aerodynamic torque of the wind turbine; _Tg is the electromagnetic torque of the generator rotor; _θr is the angular displacement of the fan rotor; _θg is the angular displacement of the generator rotor; θ is the angular displacement difference between the fan rotor and the generator rotor; _ωr is the angular velocity of the fan rotor; is the derivative of the angular velocity of the fan rotor; ω _g is the angular velocity of the generator rotor; is the derivative of the angular velocity of the generator rotor; _Ng is the gear ratio of the gearbox; A is the stiffness coefficient of the equivalent intermediate shaft; B is the damping coefficient of the equivalent intermediate shaft;

The variable pitch model is expressed by the following formula:

ω _ref =K _w ×(P _g,0 +ΔP _ref )

in, is the first-order pitch angle derivative of the variable pitch model, and the variable pitch model is a first-order inertia link with amplitude limiting and speed limiting; τ _β is the time constant of the first-order inertia link; β _ref is the pitch angle reference value; β is the pitch angle; K _P is the proportional coefficient of the first-order inertia link; ω _r is the angular velocity of the fan rotor; ω _ref is the reference angular velocity of the fan rotor; K _I is the integral coefficient of the first-order inertia link; is the derivative of φ, which is the difference between the angular velocity of the wind turbine rotor and the reference angular velocity of the wind turbine rotor; K _W is the proportionality coefficient between the angular velocity of the wind turbine rotor and the output power; P _g,0 is the initial output power of the generator rotor of the wind turbine; ΔP _ref is the reference output power change of the generator rotor;

The standard state space expression of the wind turbine is:

ΔP _g = P _g - P _g.0

Wherein, a is the coefficient corresponding to the angular velocity of the wind turbine rotor, b is the coefficient corresponding to the pitch angle, c is the coefficient corresponding to the wind speed, and d is the constant term of the linear formula; _Pg is the output power of the generator rotor of the wind turbine; _ΔPg is the output power change of the generator rotor of the wind turbine; is the derivative of the angular displacement difference between the wind turbine rotor and the generator rotor, and ω _r , ω _g , θ, φ, β and T _g are preset state parameters.

Optionally, the relationship between the electromagnetic torque and the reference output power variation is:

Where, _Tg is the electromagnetic torque of the generator rotor; is the derivative of the electromagnetic torque of the generator rotor; τ _g is the generator constant; T _ref is the reference electromagnetic torque of the wind generator; K is the proportionality coefficient between the electromagnetic torque and the output power; P _g,0 is the initial output power of the generator rotor of the wind generator; ΔP _ref is the reference output power change of the generator rotor;

The relationship between the output power of the wind turbine and the electromagnetic matrix variables is:

P _g =η×T _g ×ω _g =P _g.0 +η×T _g.0 ×Δω _g +η×ΔT _g ×ω _g.0

Δω _g =ω _g -ω _g.0

ΔT _g = T _g - T _g.0

Wherein, η is the generator efficiency; ω _g is the angular velocity of the generator rotor; T _g.0 is the initial electromagnetic torque of the generator rotor; Δω _g is the change in angular velocity of the generator rotor; ΔT _g is the change in electromagnetic torque of the generator rotor; ω _g.0 is the initial angular velocity of the generator rotor;

The expression of the first-order inertia link of the pitch angle in the variable pitch model when the pitch angle variable is zero is:

Wherein, β _ref is the pitch angle reference value, which is zero; is the first-order pitch angle derivative of the variable pitch model, wherein the variable pitch model is a first-order inertia link containing amplitude limitation and speed limitation; τ _β is the time constant of the first-order inertia link; β is the pitch angle;

The first state space expression is:

Wherein, a is the coefficient corresponding to the angular velocity of the wind turbine rotor, b is the coefficient corresponding to the pitch angle, c is the coefficient corresponding to the wind speed, and d is the constant term of the linear formula; ω _r is the angular velocity of the wind turbine rotor; is the derivative of the angular velocity of the fan rotor; ω _g is the angular velocity of the generator rotor; is the derivative of the angular velocity of the generator rotor; θ is the angular displacement difference between the fan rotor and the generator rotor; is the derivative of the angular displacement difference between the fan rotor and the generator rotor; is the derivative of φ, which is the difference between the angular velocity of the wind turbine rotor and the reference angular velocity of the wind turbine rotor; _V0 is the initial wind speed; _Jr is the moment of inertia of the wind turbine rotor; _Jg is the moment of inertia of the generator rotor of the wind turbine; _Ng is the gearbox speed ratio; A is the stiffness coefficient of the equivalent intermediate shaft; B is the damping coefficient of the equivalent intermediate shaft.

Optionally, the relationship between the pitch angle derivative and the reference output power variation is:

in, is the first-order pitch angle derivative of the variable pitch model, and the variable pitch model is a first-order inertia link with amplitude limitation and speed limitation; τ _β is the time constant of the first-order inertia link; β is the pitch angle; K _P is the proportional coefficient of the first-order inertia link; ω _r is the angular velocity of the fan rotor; K _I is the integral coefficient of the first-order inertia link; is the derivative of φ, which is the difference between the angular velocity of the wind turbine rotor and the reference angular velocity of the wind turbine rotor; K _W is the proportionality coefficient between the angular velocity of the wind turbine rotor and the output power; P _g,0 is the initial output power of the generator rotor of the wind turbine; ΔP _ref is the reference output power change of the generator rotor;

The relationship between the output power and the initial output power is:

Wherein, _Pg is the output power of the generator rotor of the wind turbine; η is the generator efficiency; _ωg is the angular velocity of the generator rotor; _Pg.0 is the initial output power of the generator rotor of the wind turbine; _ωg.0 is the initial angular velocity of the generator rotor;

The relationship between the electromagnetic torque and the reference electromagnetic torque when the electromagnetic torque variable is zero is expressed as:

Where, _Tg is the electromagnetic torque of the generator rotor; is the derivative of the electromagnetic torque of the generator rotor; τ _g is the generator constant; T _g.0 is the initial electromagnetic torque of the generator rotor; ω _g.0 is the initial angular velocity of the generator rotor;

The second state space expression is:

Wherein, a is the coefficient corresponding to the angular velocity of the wind turbine rotor, b is the coefficient corresponding to the pitch angle, c is the coefficient corresponding to the wind speed, and d is the constant term of the linear formula; ω _r is the angular velocity of the wind turbine rotor; is the derivative of the angular velocity of the fan rotor; ω _g is the angular velocity of the generator rotor; is the derivative of the angular velocity of the generator rotor; θ is the angular displacement difference between the fan rotor and the generator rotor; is the derivative of the angular displacement difference between the fan rotor and the generator rotor; is the derivative of φ, which is the difference between the angular velocity of the wind turbine rotor and the reference angular velocity of the wind turbine rotor; _V0 is the initial wind speed; _Jr is the moment of inertia of the wind turbine rotor; _Jg is the moment of inertia of the generator rotor of the wind turbine; _Ng is the gearbox speed ratio; A is the stiffness coefficient of the equivalent intermediate shaft; B is the damping coefficient of the equivalent intermediate shaft.

In a second aspect, an embodiment of the present application further provides a wind turbine primary frequency modulation simulation device, the device comprising: an acquisition module for acquiring a reference output power change for controlling the wind turbine to perform primary frequency modulation; a construction module for constructing a preset state space expression corresponding to the preset wind speed range based on a relationship between the electromagnetic torque of the wind turbine and the electromagnetic torque variable in a preset wind speed range, in combination with a double-mass model and a variable pitch model of the wind turbine, wherein the preset state space expression is used to characterize the relationship between the preset state variables of the wind turbine and the reference output power change in the preset wind speed range; a determination module for determining a target state space expression corresponding to the target wind speed range based on the target wind speed range to which the current wind speed belongs; and a calculation module for substituting the reference output power change into the target state space expression to calculate the preset state variables of the primary frequency modulation, so as to perform a primary frequency modulation simulation on the wind turbine.

In a third aspect, an embodiment of the present application further provides an electronic device, comprising: a processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor and the memory communicate through the bus, and the machine-readable instructions are executed by the processor to execute the steps of the wind turbine primary frequency regulation simulation method described in the first aspect or any possible implementation manner of the first aspect.

In a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the wind turbine primary frequency regulation simulation method described in the first aspect or any possible implementation manner of the first aspect are executed.

A method and device for simulating primary frequency modulation of a wind turbine provided in an embodiment of the present application, the method comprising: obtaining a reference output power variation for controlling the wind turbine to perform primary frequency modulation; constructing a preset state space expression corresponding to the preset wind speed interval based on a relationship between the electromagnetic torque of the wind turbine and the electromagnetic torque variable in a preset wind speed interval, in combination with a double-mass model and a variable pitch model of the wind turbine, wherein the preset state space expression is used to characterize the relationship between the preset state variable of the wind turbine and the reference output power variation in the preset wind speed interval; determining a target state space expression corresponding to the target wind speed interval based on a target wind speed interval to which a current wind speed belongs; substituting the reference output power variation into the target state space expression, and calculating the preset state variable for primary frequency modulation to control the wind turbine to perform primary frequency modulation. The power variation during the primary frequency modulation of the wind turbine is converted into a state space expression corresponding to the preset state parameters in different wind speed ranges, thereby converting the power variation into a linear expression related to the preset state parameters. When the reference output power variation of the output power of the generator is received, a preset state parameter is calculated according to the state space expression corresponding to the wind speed range to which the current wind speed belongs. The wind turbine is simulated to operate according to the calculated preset state parameters to simulate the primary frequency modulation of the wind turbine, thereby solving the technical problems in the prior art of requiring a large amount of data for primary frequency modulation simulation and the overly complex model to be constructed, thereby achieving the technical effect of improving the efficiency of primary frequency modulation simulation of the wind turbine.

In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

FIG1 shows a flow chart of a method for simulating primary frequency regulation of a wind turbine provided in an embodiment of the present application.

FIG2 shows a functional module diagram of a wind turbine primary frequency regulation simulation device provided in an embodiment of the present application.

FIG3 shows a schematic structural diagram of an electronic device provided in an embodiment of the present application.

DETAILED DESCRIPTION

To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the drawings in the present application only serve the purpose of explanation and description and are not used to limit the scope of protection of the present application. In addition, it should be understood that the schematic drawings are not drawn in real proportion. The flowchart used in this application shows the operations implemented according to some embodiments of the present application. It should be understood that the operations of the flowchart can be implemented out of sequence, and the steps without logical context can be reversed in order or implemented simultaneously. In addition, those skilled in the art, under the guidance of the content of the present application, can add one or more other operations to the flowchart, or remove one or more operations from the flowchart.

In addition, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

In the prior art, a "black box model" driven by input-output data is used to predict how the various data of the generator should change when the output power changes. This prediction method requires a large amount of data; or a "white box modeling" based on mechanism analysis is used to predict how the various data of the generator should change when the output power changes. The model of this prediction method is relatively complex and difficult to apply.

Based on this, the embodiment of the present application provides a method and device for simulating primary frequency modulation of a wind turbine generator, by converting the power variation during the primary frequency modulation of the wind turbine generator into state space expressions corresponding to preset state parameters in different wind speed intervals, so as to convert the power variation into a linear expression related to the preset state parameters, so that when receiving the reference output power variation of the output power of the generator, a preset state parameter is calculated according to the state space expression corresponding to the wind speed interval to which the current wind speed belongs, so that the wind turbine generator simulates operation according to the calculated preset state parameters to simulate the primary frequency modulation of the wind turbine generator, thereby solving the technical problems in the prior art that a large amount of data is required for primary frequency modulation simulation and the constructed model is too complex, and the technical effect of improving the efficiency of primary frequency modulation simulation of the wind turbine generator is achieved, which is as follows:

Please refer to Figure 1, which is a flow chart of a wind turbine primary frequency modulation simulation method provided in an embodiment of the present application. As shown in Figure 1, the wind turbine primary frequency modulation simulation method provided in an embodiment of the present application includes the following steps:

S101: Obtaining a reference output power variation for controlling a wind turbine generator to perform a frequency modulation.

The reference output power variation ΔP _ref is the variation based on the initial output power P _g.0 of the wind turbine generator, and the output power after the variation P _g = P _g.0 ± ΔP _ref . The reference output power variation refers to the theoretical transformation amount of the wind turbine generator, and the actual output power variation is equal to the reference output power variation.

Before obtaining the reference output power variation for controlling the wind turbine to perform a frequency modulation, the wind turbine is in a steady state. At this time, the initial wind turbine rotor speed of the wind turbine is ω _r.0 , the initial electromagnetic torque of the wind turbine is T _g.0 , the output initial electromagnetic power P _g,0 is equal to the initial electromagnetic power reference value _Pref,0 , and the wind speed at this time is the initial wind speed V ₀ .

When the frequency of the power grid changes, or the voltage output by the power grid is unstable, the output power of the wind turbine needs to be adjusted. At this time, a reference output power change ΔP _ref for performing a frequency modulation will be sent to the wind turbine, and it will be informed whether to increase ΔP _ref or decrease ΔP _ref , so that the wind turbine can make adjustments based on ΔP _ref , so that the wind turbine can re-enter a steady state.

S102: Based on the relationship between the electromagnetic torque and the electromagnetic torque variable of the wind turbine in the preset wind speed range, combined with the double-mass model and the variable pitch model of the wind turbine, a preset state space expression corresponding to the preset wind speed range is constructed.

The preset state space expression is used to characterize the relationship between the preset state variable of the wind turbine generator and the reference output power variation in a preset wind speed range.

The preset wind speed interval includes a first preset interval and a second preset interval, the upper limit value of the first preset interval is equal to the lower limit value of the second preset interval, and the preset state space expression includes a first state space expression corresponding to the first preset interval and a second state space expression corresponding to the second preset interval.

Wherein, when the preset wind speed interval is the first preset interval, the first state space expression is used to characterize the relationship between the preset state variable of the wind turbine and the reference output power change when only the electromagnetic torque of the wind turbine is changed. When the preset wind speed interval is the second preset interval, the second state space expression is used to characterize the relationship between the preset state variable of the wind turbine and the reference output power change when only the pitch angle of the wind turbine is changed.

Among them, the upper limit value of the first preset interval and the lower limit value of the second preset interval are the rated wind speed. When the current wind speed of the wind turbine is the rated wind speed V _rated , the output power of the wind turbine can be changed by changing the electromagnetic torque or pitch angle of the wind turbine. Therefore, the rated wind speed can be classified into the first preset interval or the second preset interval.

Exemplarily, the first preset interval is an open interval greater than the minimum operating wind speed V _min and less than the rated wind speed V _rated , and the second preset interval is a left-closed and right-open interval greater than or equal to the rated wind speed and less than the maximum operating wind speed V _max , that is, the first preset interval is (V _min , V _rated ), and the second preset interval is [V _rated , V _max ); or, the first preset interval is a left-open and right-closed interval greater than the minimum operating wind speed V _min and less than or equal to the rated wind speed V _rated , and the second preset interval is an open interval greater than the rated wind speed and less than the maximum operating wind speed V _max , that is, the first preset interval is (V _min , V _rated ], and the second preset interval is (V _rated , V _max ). The rated wind speed V _rated can be determined according to the model of the wind turbine, and is generally set to 11.4 meters per second.

When the current wind speed is less than or equal to the minimum operating wind speed V _min , or when the current wind speed is greater than or equal to the maximum operating wind speed V _max , the wind turbine stops working.

That is to say, when the current wind speed belongs to the first preset range, the output power of the wind generator is changed by the reference output power change by changing the electromagnetic torque of the wind generator; when the current wind speed belongs to the second preset range, the output power of the wind generator is changed by changing the pitch angle of the wind generator.

The preset state space expression corresponding to the preset wind speed range is constructed in the following way:

According to the aerodynamic torque formula of the fan blade, a linear formula related to the aerodynamic torque and a plurality of preset parameters is constructed, each preset parameter being a parameter in the aerodynamic torque formula of the fan blade and a parameter that changes during the power generation process;

The linear equation that relates the aerodynamic torque to several preset parameters is constructed using the following formula:

T _r =a×ω _r +b×β+c×V+d(4)

In formulas (1) to (4), _Pr is the aerodynamic power of the wind turbine, ρ is the air density, R is the radius of the wind turbine rotor, V is the wind speed, _Cp (λ, β) is the wind energy utilization coefficient, λ is the tip speed ratio of the wind turbine rotor, β is the pitch angle, _ωr is the wind turbine rotor speed, _Tr is the aerodynamic torque of the wind turbine, _ωr , β and V are all preset parameters, a is the coefficient corresponding to _ωr , b is the coefficient corresponding to β, c is the coefficient corresponding to V, and d is the constant term of the linear formula.

Among them, C _P (λ, β) is a high-order nonlinear function between the tip speed ratio and the pitch angle. In other words, combined with formula (3), it can be seen that T _r in the aerodynamic system is a highly nonlinear function of ω _r , β and V, which is difficult to describe with a simple mathematical model. Then, it can be simplified by linearization. This paper selects the PWA model (Piece Wise Affine) to divide different operating conditions and use a linear model to approximate the nonlinear characteristics of aerodynamic power, thereby obtaining formula (4).

The different operating conditions divided in the present application are divided into the current wind speed belonging to the first preset interval or the second preset interval. When the current wind speed belongs to the first preset interval, the first state space expression corresponding to the first preset interval is used to predict the various preset state parameters when the output power changes by the reference output power change amount; when the current wind speed belongs to the second preset interval, the second state space expression corresponding to the second preset interval is used to predict the various preset state parameters when the output power changes by the reference output power change amount.

According to the relationship between the electromagnetic torque of the wind turbine and the reference electromagnetic torque, combined with the linear formula, the double-mass model and the variable pitch model of the wind turbine, a standard state space expression of the wind turbine is constructed.

The standard state space expression is used to characterize the relationship between the preset state parameters of the wind turbine and the changes corresponding to the multiple preset parameters, as well as the relationship between the output power of the wind turbine and the initial output power. The preset state parameters are parameters that change during the power generation process.

Since the electromagnetic transient process of the generator is usually only in the millisecond level, the variable frequency drive model consisting of the generator and the inverter in the generator system can be accurately replaced by a first-order linear link.

Furthermore, the relationship between the electromagnetic torque of the wind turbine and the reference electromagnetic torque is:

In formula (5), _Tg is the electromagnetic torque of the generator rotor; is the derivative of the electromagnetic torque of the generator rotor; τ _g is the generator constant; T _ref is the reference electromagnetic torque of the wind generator, that is, the electromagnetic torque of the wind generator in theory. After the actual transformation, the electromagnetic torque of the wind generator is equal to the reference battery torque.

Since the electromagnetic torque is proportional to the output power, and the reference output power _Pref = _ΔPref + _Pg.0 , wherein _ΔPref is the reference output power variation, and _Pg.0 is the initial output power.

Furthermore, the expression between the reference electromagnetic torque and the reference output power change is:

T _ref =K×P _ref =K×ΔP _ref +K×P _g.0 (6)

In formula (6), T _ref is the reference electromagnetic torque of the generator rotor; K is the proportionality coefficient between the electromagnetic torque and the output power; _Pref is the reference output power; _Pg,0 is the initial output power of the generator rotor of the wind turbine; ΔP _ref is the reference output power change of the generator rotor.

Substituting formula (6) into formula (5), the relationship between the electromagnetic torque and the reference output power change is:

In formula (7), _Tg is the electromagnetic torque of the generator rotor; is the derivative of the electromagnetic torque of the generator rotor; τ _g is the generator constant; T _ref is the reference electromagnetic torque of the wind generator; K is the proportional coefficient between the electromagnetic torque and the output power; P _g,0 is the initial output power of the generator rotor of the wind generator; ΔP _ref is the reference output power change of the generator rotor.

The dual mass model is represented by the following formula:

In formula (8), J _r is the moment of inertia of the fan rotor of the wind turbine; J _g is the moment of inertia of the generator rotor of the wind turbine; T _shaft is the equivalent intermediate shaft torque between the fan rotor and the generator rotor; _Tr is the aerodynamic torque of the wind turbine; T _g is the electromagnetic torque of the generator rotor; θ _r is the angular displacement of the fan rotor; θ _g is the angular displacement of the generator rotor; θ is the angular displacement difference between the fan rotor and the generator rotor; ω _r is the angular velocity of the fan rotor; is the derivative of the angular velocity of the fan rotor; ω _g is the angular velocity of the generator rotor; is the derivative of the angular velocity of the generator rotor; _Ng is the gear ratio of the gearbox; A is the stiffness coefficient of the equivalent intermediate shaft; B is the damping coefficient of the equivalent intermediate shaft.

Then, taking the derivative of θ, we can get:

The double-mass model is a method in which the mechanical energy generated by the wind turbine rotor is first transmitted to the low-speed shaft of the gearbox, and then transmitted to the generator rotor by the high-speed shaft after the speed change of the gearbox, so as to realize the movement of the generator rotor by rotating the wind turbine rotor, thereby converting wind energy into electrical energy.

The variable pitch model is expressed by the following formula:

Formula (10), is the first-order pitch angle derivative of the variable pitch model, and the variable pitch model is a first-order inertia link containing amplitude limitation and speed limitation; τ _β is the time constant of the first-order inertia link; β _ref is the pitch angle reference value; β is the pitch angle.

The expression between the angular velocity of the fan rotor and the reference angular velocity of the fan rotor is:

β _ref =K _P ×(ω _r -ω _ref )+K _I ×∫(ω _r -ω _ref ) =K _P ×(ω _r -ω _ref )+K _I ×φ (11)

In formula (11), K _P is the proportional coefficient of the first-order inertia link; ω _r is the angular velocity of the fan rotor; ω _ref is the reference angular velocity of the fan rotor; K _I is the integral coefficient of the first-order inertia link; is the derivative of φ, which is the difference between the angular velocity of the fan rotor and the reference angular velocity of the fan rotor; K _W is the proportional coefficient between the angular velocity of the fan rotor and the output power.

That is, to write it as a linear expression, we set φ = ∫ (ω _r - ω _ref ), and then we get:

The expression between the reference angular velocity and the reference output power change is:

ω _ref =K _W ×(P _g,0 +ΔP _ref ) (13)

In formula (13), ω _ref is the reference angular velocity of the wind turbine rotor; K _W is the proportionality coefficient between the angular velocity of the wind turbine rotor and the output power; P _g,0 is the initial output power of the generator rotor of the wind turbine; ΔP _ref is the reference output power change of the generator rotor.

Substituting formulas (11) and (13) into formula (10) yields the expression between the first-order pitch angle derivative of the variable pitch model and the reference output power change:

In formula (14), K _P is the proportional coefficient of the first-order inertia link; ω _r is the angular velocity of the fan rotor; ω _ref is the reference angular velocity of the fan rotor; K _I is the integral coefficient of the first-order inertia link; is the derivative of φ, which is the difference between the angular velocity of the wind turbine rotor and the reference angular velocity of the wind turbine rotor; K _W is the proportionality coefficient between the angular velocity of the wind turbine rotor and the output power; P _g,0 is the initial output power of the generator rotor of the wind turbine; ΔP _ref is the reference output power change of the generator rotor.

Combining formula (5), formula (8), formula (9), formula (10) and formula (12), the standard state space expression of the wind turbine can be obtained.

The standard state space expression of the wind turbine is:

In formula (15), a is the coefficient corresponding to the angular velocity of the wind turbine rotor, b is the coefficient corresponding to the pitch angle, c is the coefficient corresponding to the wind speed, and d is the constant term of the linear formula; _Pg is the output power of the generator rotor of the wind turbine; _ΔPg is the output power change of the generator rotor of the wind turbine; is the derivative of the angular displacement difference between the wind turbine rotor and the generator rotor; ω _r , ω _g , θ, φ, β and T _g are preset state parameters.

That is, the derivative corresponding to each preset state parameter is written in the form of a state space expression, so that the derivative corresponding to each preset state parameter is related to the preset parameter (the preset parameters in this case are ω _ref , β _ref , T _ref ).

Among them, when only the electromagnetic torque of the wind turbine is changed, the first state space expression is constructed by the relationship between the electromagnetic torque and the reference output power change, the standard state space expression and the first-order inertia link expression of the pitch angle in the variable pitch model when the pitch angle reference value is zero.

That is to say, when the current wind speed belongs to the first preset interval, only the electromagnetic torque of the wind generator is changed without changing the pitch angle, so the value of β _ref is 0 and has nothing to do with the reference angular velocity ω _ref of the wind turbine rotor.

At this time, the relationship between the output power of the wind turbine and the electromagnetic matrix variable is:

P _g ＝η×T _g ×ω _g ＝P _g.0 +η×T _g.0 ×Δω _g +η×ΔT _g ×ω _g.0 (16)

Δω _g =ω _g -ω _g.0 (17)

ΔT _g = T _g - T _g.0 (18)

In formulas (16) to (18), η is the generator efficiency; ω _g is the angular velocity of the generator rotor; T _g.0 is the initial electromagnetic torque of the generator rotor; Δω _g is the change in angular velocity of the generator rotor, and; ΔT _g is the change in electromagnetic torque of the generator rotor; ω _g.0 is the initial angular velocity of the generator rotor.

P _g.0 = η×T _g.0 ×ω _g.0 (19)

Substituting formula (17) and (18) into formula (16), we can obtain:

P _g ＝P _g.0 +η×T _g.0 ×ω _g +η×T _g ×ω _g.0 -2×η×T _g.0 ×ω _g.0

=-P _g.0 +η×T _g.0 ×ω _g +η×T _g ×ω _g.0 (20)

Furthermore, ΔP _g =P _g -P _g.0 =-2×P _g.0 +η×T _g.0 ×ω _g +η×T _g ×ω _g.0 .

The expression of the first-order inertia link of the pitch angle in the variable pitch model when the pitch angle variable is zero is:

In formula (21), β _ref is the pitch angle reference value, which is zero; is the first-order pitch angle derivative of the variable pitch model, and the variable pitch model is a first-order inertia link containing amplitude limitation and speed limitation; τ _β is the time constant of the first-order inertia link; β is the pitch angle.

Furthermore, by combining formula (7), formula (15), formula (20) and formula (21), the first state space expression can be obtained:

In formula (22), a is the coefficient corresponding to the angular velocity of the wind turbine rotor, b is the coefficient corresponding to the pitch angle, c is the coefficient corresponding to the wind speed, and d is the constant term of the linear formula; ω _r is the angular velocity of the wind turbine rotor; is the derivative of the angular velocity of the fan rotor; ω _g is the angular velocity of the generator rotor; is the derivative of the angular velocity of the generator rotor; θ is the angular displacement difference between the fan rotor and the generator rotor; is the derivative of the angular displacement difference between the fan rotor and the generator rotor; is the derivative of φ, which is the difference between the angular velocity of the wind turbine rotor and the reference angular velocity of the wind turbine rotor; _V0 is the initial wind speed; _Jr is the moment of inertia of the wind turbine rotor; _Jg is the moment of inertia of the generator rotor of the wind turbine; _Ng is the gearbox speed ratio; A is the stiffness coefficient of the equivalent intermediate shaft; B is the damping coefficient of the equivalent intermediate shaft.

The initial wind speed can be understood as the wind speed of the wind turbine in a steady state before obtaining the reference output power variation for controlling the wind turbine to perform a frequency modulation. When only the pitch angle of the wind turbine is changed, the second state space expression is constructed by the relationship between the pitch angle derivative and the reference output power variation, the standard state space expression, the relationship between the output power and the initial electromagnetic torque, and the relationship between the electromagnetic torque and the reference electromagnetic torque when the electromagnetic torque variable is zero.

That is to say, when the current wind speed belongs to the second preset interval, the output power is changed only by changing the pitch angle.

When the current wind speed belongs to the second preset interval, the wind turbine generator is in a power-limited state, and the electromagnetic torque remains unchanged at the initial value.

The relationship between the output power and the initial output power is:

In formula (23), _Pg is the output power of the generator rotor of the wind turbine; η is the generator efficiency; _ωg is the angular velocity of the generator rotor; _Pg.0 is the initial output power of the generator rotor of the wind turbine; _ωg.0 is the initial angular velocity of the generator rotor.

The relationship between the electromagnetic torque and the reference electromagnetic torque when the electromagnetic torque variable is zero is expressed as:

In formula (24), _Tg is the electromagnetic torque of the generator rotor; is the derivative of the electromagnetic torque of the generator rotor; τ _g is the generator constant; T _g.0 is the initial electromagnetic torque of the generator rotor; ω _g.0 is the initial angular velocity of the generator rotor.

Combining formula (12), formula (13), formula (14), formula (23) and formula (24), the second state space expression is obtained:

In formula (25), a is the coefficient corresponding to the angular velocity of the wind turbine rotor, b is the coefficient corresponding to the pitch angle, c is the coefficient corresponding to the wind speed, and d is the constant term of the linear formula; ω _r is the angular velocity of the wind turbine rotor; is the derivative of the angular velocity of the fan rotor; ω _g is the angular velocity of the generator rotor; is the derivative of the angular velocity of the generator rotor; θ is the angular displacement difference between the fan rotor and the generator rotor; is the derivative of the angular displacement difference between the fan rotor and the generator rotor; is the derivative of φ, which is the difference between the angular velocity of the wind turbine rotor and the reference angular velocity of the wind turbine rotor; _V0 is the initial wind speed; _Jr is the moment of inertia of the wind turbine rotor; _Jg is the moment of inertia of the generator rotor of the wind turbine; _Ng is the gearbox speed ratio; A is the stiffness coefficient of the equivalent intermediate shaft; B is the damping coefficient of the equivalent intermediate shaft.

S103: Determine a target state space expression corresponding to the target wind speed interval according to the target wind speed interval to which the current wind speed belongs.

The target wind speed interval is one of the first preset interval and the second preset interval, and the target state space expression is one of the first state space expression and the second state space expression.

The current wind speed may be understood as the wind speed when obtaining the reference output power variation for controlling the wind turbine generator to perform a frequency modulation.

Furthermore, when the current wind speed belongs to the first preset interval, the target wind speed interval is the first preset interval, and the target state space expression is determined to be the first state space expression, that is, when only the electromagnetic torque of the wind generator is changed, the state space expression between the reference output power change and each preset state variable is determined.

When the current wind speed belongs to the second preset interval, the target wind speed interval is the second preset interval, and then the target state space expression is determined to be the second state space expression, that is, when only the pitch angle of the wind turbine is changed, the state space expression between the reference output power change and each preset state variable is determined.

S104: Substituting the reference output power variation into the target state space expression, calculating a preset state variable of a primary frequency modulation, so as to perform a primary frequency modulation simulation on the wind turbine generator.

Therefore, after determining the target state space expression, the reference output power change is substituted into the target state space expression to determine the value of each preset state variable, thereby controlling the wind turbine to simulate according to the calculated preset state variables to simulate the primary frequency modulation of the wind turbine.

Exemplarily, the first state space expression can also be simplified as:

in, x＝[ω _r ω _g θ φ β T _g ] ^T , u＝ΔP _ref ， v＝[V ₀ P _g.0 ] ^T ， y＝ΔP _g ， F ₁ = -2×P _g.0 .

Exemplarily, the second state space expression can also be simplified as:

in, x＝[ω _r ω _g θφβT _g ] ^T , u＝Δp _ref ， v＝[V ₀ p _g.0 ] ^T ， y＝ΔP _g ， _F2 = _-Pg.0 .

Furthermore, considering that the low-order mechanism model has a limited degree of approximation to complex nonlinearity, a neural network algorithm can be introduced to compensate for the deviation of the mechanism model. The neural network model is used to predict the first compensation and the second compensation. The state space expression based on the neural network model is:

In formula (27), _Ai , _Bi , _Ci , _Di , _Ei , and _Fi correspond to the first state space expression or the second state space expression, f is the first compensation, and g is the second compensation.

That is, the “black box model” driven by input-output data or the “white box modeling” based on mechanism analysis predicts The predicted value in the first state space expression or the second state space expression is subtract the predicted y from the first state space expression or the second state space expression to obtain a second difference; subtract the predicted y from the "black box model" driven by input-output data or the "white box modeling" based on mechanism analysis to obtain a second difference, and then and y as sample data, and use the corresponding first difference and second difference as labels to train the neural network model, so that the neural network model can predict the first difference and the second difference, that is, predict the first compensation and the second compensation, and then get a more accurate result without using "black box model" or "white box modeling". and y, so as to obtain a more accurate x = [ω _r ω _g θφβT _g ] ^T .

Since the system state quantities in the above continuous state-space equations are observable, the joint identification of the wind turbine mechanism parameters in the above state-space equations and the data parameters in the PWA model can be completed based on the operating data in the actual working domain of the wind turbine. In other words, the stiffness coefficient A of the equivalent intermediate shaft, the damping coefficient B of the equivalent intermediate shaft and other coefficients may have inaccurate values due to the age of use, etc., so through joint identification, it is convenient to obtain more accurate A and B, making the calculated preset state variables more accurate, thereby achieving the sub-regional transient characteristics of multiple sub-models approaching the global nonlinear transient characteristics of the system.

Based on the same application concept, the embodiment of the present application also provides a wind turbine primary frequency regulation simulation device corresponding to the wind turbine primary frequency regulation simulation method provided in the above embodiment. Since the principle of solving the problem by the device in the embodiment of the present application is similar to the wind turbine primary frequency regulation simulation method in the above embodiment of the present application, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be repeated.

As shown in Figure 2, Figure 2 is a functional module diagram of a wind turbine primary frequency regulation simulation device provided in an embodiment of the present application. The wind turbine primary frequency regulation simulation device 10 includes: an acquisition module 101, a construction module 102, a determination module 103 and a calculation module 104.

An acquisition module 101 is used to acquire a reference output power variation for controlling a wind turbine to perform a primary frequency modulation; a construction module 102 is used to construct a preset state space expression corresponding to the preset wind speed interval based on a relationship between the electromagnetic torque of the wind turbine and the electromagnetic torque variable in a preset wind speed interval, in combination with a double-mass model and a variable pitch model of the wind turbine, wherein the preset state space expression is used to characterize the relationship between the preset state variable of the wind turbine and the reference output power variation in the preset wind speed interval; a determination module 103 is used to determine a target state space expression corresponding to the target wind speed interval according to the target wind speed interval to which the current wind speed belongs; and a calculation module 104 is used to substitute the reference output power variation into the target state space expression to calculate the preset state variable for a primary frequency modulation, so as to perform a primary frequency modulation simulation on the wind turbine.

Based on the same application concept, referring to FIG3 , which is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application, the electronic device 20 comprises: a processor 201, a memory 202 and a bus 203, wherein the memory 202 stores machine-readable instructions executable by the processor 201, and when the electronic device 20 is running, the processor 201 communicates with the memory 202 through the bus 203, and the machine-readable instructions are executed by the processor 201 when running, as in the steps of the primary frequency modulation simulation method of a wind turbine as described in any of the above embodiments.

Specifically, when the machine-readable instructions are executed by the processor 201, the following processing can be performed: obtaining a reference output power change for controlling the wind turbine to perform a single frequency modulation; constructing a preset state space expression corresponding to the preset wind speed range based on the relationship between the electromagnetic torque and the electromagnetic torque variable of the wind turbine in the preset wind speed range, combined with the double-mass model and the variable pitch model of the wind turbine, the preset state space expression is used to characterize the relationship between the preset state variables of the wind turbine and the reference output power change in the preset wind speed range; determining a target state space expression corresponding to the target wind speed range based on the target wind speed range to which the current wind speed belongs; substituting the reference output power change into the target state space expression, and calculating the preset state variables for a single frequency modulation to perform a single frequency modulation simulation on the wind turbine.

Based on the same application concept, an embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the wind turbine primary frequency modulation simulation method provided in the above embodiment are executed.

Specifically, the storage medium can be a general storage medium, such as a mobile disk, a hard disk, etc. When the computer program on the storage medium is run, the above-mentioned wind turbine primary frequency modulation simulation method can be executed, by converting the power change during the primary frequency modulation of the wind turbine into a state space expression corresponding to the preset state parameters in different wind speed intervals, so as to convert the power change into a linear expression related to the preset state parameters, so that when the reference output power change of the output power of the generator is received, a preset state parameter is calculated according to the state space expression corresponding to the wind speed interval to which the current wind speed belongs, so that the wind turbine is simulated according to the calculated preset state parameters to simulate the primary frequency modulation of the wind turbine, thereby solving the technical problems in the prior art that a large amount of data is required for primary frequency modulation simulation and the constructed model is too complicated, and the technical effect of improving the efficiency of primary frequency modulation simulation of the wind turbine is achieved, as well as the technical effect of simplifying the model.

Those skilled in the art can clearly understand that, for the convenience and simplicity of description, the specific working process of the system and device described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here. In the several embodiments provided in the present application, it should be understood that the disclosed system, device and method can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory, ROM), random access memory (Random Access Memory, RAM), disk or optical disk and other media that can store program codes.

The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims (9)

1. A method for simulating primary frequency modulation of a wind turbine generator, characterized in that the method comprises: Obtaining a reference output power variation for controlling a wind turbine generator to perform a frequency modulation; According to the relationship between the electromagnetic torque of the wind turbine and the reference electromagnetic torque in the preset wind speed range, combined with the double-mass model and the variable pitch model of the wind turbine, a preset state space expression corresponding to the preset wind speed range is constructed, and the preset state space expression is used to characterize the relationship between the preset state variable of the wind turbine and the reference output power change in the preset wind speed range; Determine a target state space expression corresponding to the target wind speed interval according to the target wind speed interval to which the current wind speed belongs; Substituting the reference output power variation into the target state space expression, calculating the preset state variable of the primary frequency modulation, so as to perform a primary frequency modulation simulation on the wind turbine; The preset wind speed interval includes a first preset interval and a second preset interval, the upper limit value of the first preset interval is equal to the lower limit value of the second preset interval, the preset state space expression includes a first state space expression corresponding to the first preset interval and a second state space expression corresponding to the second preset interval, the target wind speed interval is one of the first preset interval and the second preset interval, and the target state space expression is one of the first state space expression and the second state space expression. Wherein, when the preset wind speed interval is the first preset interval, the first state space expression is used to characterize the relationship between the preset state variable of the wind generator and the reference output power variation when only the electromagnetic torque of the wind generator is changed; When the preset wind speed interval is the second preset interval, the second state space expression is used to characterize the relationship between the preset state variable of the wind turbine and the reference output power variation when only the pitch angle of the wind turbine is changed. 2. The method according to claim 1, characterized in that the preset state space expression corresponding to the preset wind speed interval is constructed in the following manner: According to the aerodynamic torque formula of the fan blade, a linear formula related to the aerodynamic torque and a plurality of preset parameters is constructed, each preset parameter being a parameter in the aerodynamic torque formula of the fan blade and a parameter that changes during the power generation process; According to the relationship between the electromagnetic torque of the wind turbine and the reference electromagnetic torque, in combination with the linear formula, the double-mass model and the variable pitch model of the wind turbine, a standard state space expression of the wind turbine is constructed, wherein the standard state space expression is used to characterize the relationship between the preset state parameters of the wind turbine and the changes respectively corresponding to the plurality of preset parameters, and the relationship between the output power of the wind turbine and the initial output power, wherein the preset state parameters are parameters that change during the power generation process; Wherein, when only the electromagnetic torque of the wind turbine is changed, the first state space expression is constructed by the relational expression related to the electromagnetic torque and the reference output power variation, the standard state space expression and the first-order inertia link expression of the pitch angle in the variable pitch model when the pitch angle reference value is zero; When only the pitch angle of the wind turbine is changed, the second state-space expression is constructed by the relationship between the pitch angle derivative and the reference output power change, the standard state-space expression, the relationship between the output power and the initial output power, and the relationship between the electromagnetic torque and the reference electromagnetic torque when the electromagnetic torque change is zero. 3. The method according to claim 2, characterized in that a linear formula related to the aerodynamic torque and a plurality of preset parameters is constructed by the following formula: T _r = a×ω _r + b×β+c×V+d Wherein, P _r is the aerodynamic power of the wind turbine, ρ is the air density, R is the radius of the wind turbine rotor, V is the wind speed, _CP (λ, β) is the wind energy utilization coefficient, λ is the tip speed ratio of the wind turbine rotor, β is the pitch angle, ω _r is the wind turbine rotor speed, _Tr is the aerodynamic torque of the wind turbine, ω _r , β and V are all preset parameters, a is the coefficient corresponding to ω _r , b is the coefficient corresponding to β, c is the coefficient corresponding to V, and d is the constant term of the linear formula. 4. The method according to claim 2, characterized in that the relationship between the electromagnetic torque of the wind turbine and the reference electromagnetic torque is: Where, _Tg is the electromagnetic torque of the generator rotor; is the derivative of the electromagnetic torque of the generator rotor; τ _g is the generator constant; T _ref is the reference electromagnetic torque of the wind generator; The dual mass model is represented by the following formula: Wherein, J _r is the moment of inertia of the fan rotor of the wind turbine; J _g is the moment of inertia of the generator rotor of the wind turbine; T _shaft is the equivalent intermediate shaft torque between the fan rotor and the generator rotor; _Tr is the aerodynamic torque of the wind turbine; T _g is the electromagnetic torque of the generator rotor; θ _r is the angular displacement of the fan rotor; θ _g is the angular displacement of the generator rotor; θ is the angular displacement difference between the fan rotor and the generator rotor; ω _r is the angular velocity of the fan rotor; is the derivative of the angular velocity of the fan rotor; ω _g is the angular velocity of the generator rotor; is the derivative of the angular velocity of the generator rotor; _Ng is the gear ratio of the gearbox; A is the stiffness coefficient of the equivalent intermediate shaft; B is the damping coefficient of the equivalent intermediate shaft; The variable pitch model is expressed by the following formula: β _ref =K _P ×(ω _r -ω _ref )+K _I ×∫(ω _r -ω _ref ) =K _P ×(ω _r -ω _ref )+K _I ×φ ω _ref = K _W × (P _{g, 0} + ΔP _ref ) in, is the first-order pitch angle derivative of the variable pitch model, and the variable pitch model is a first-order inertia link with amplitude limiting and speed limiting; τ _β is the time constant of the first-order inertia link; β _ref is the pitch angle reference value; β is the pitch angle; K _P is the proportional coefficient of the first-order inertia link; ω _r is the angular velocity of the fan rotor; ω _ref is the reference angular velocity of the fan rotor; K _I is the integral coefficient of the first-order inertia link; is the derivative of φ, which is the difference between the angular velocity of the wind turbine rotor and the reference angular velocity of the wind turbine rotor; K _W is the proportionality coefficient between the angular velocity of the wind turbine rotor and the output power; P _g,0 is the initial output power of the generator rotor of the wind turbine; ΔP _ref is the reference output power change of the generator rotor; The standard state space expression of the wind turbine is: ΔP _g = P _g - P _g.0 Wherein, a is the coefficient corresponding to the angular velocity of the wind turbine rotor, b is the coefficient corresponding to the pitch angle, c is the coefficient corresponding to the wind speed, and d is the constant term of the linear formula; _Pg is the output power of the generator rotor of the wind turbine; _ΔPg is the output power change of the generator rotor of the wind turbine; is the derivative of the angular displacement difference between the wind turbine rotor and the generator rotor, and ω _r , ω _g , θ, φ, β and T _g are preset state parameters. 5. The method according to claim 2, characterized in that the relationship between the electromagnetic torque and the reference output power variation is: Where, _Tg is the electromagnetic torque of the generator rotor; is the derivative of the electromagnetic torque of the generator rotor; τ _g is the generator constant; T _ref is the reference electromagnetic torque of the wind generator; K is the proportionality coefficient between the electromagnetic torque and the output power; P _g,0 is the initial output power of the generator rotor of the wind generator; ΔP _ref is the reference output power change of the generator rotor; The relationship between the output power of the wind turbine and the electromagnetic matrix variables is as follows: P _g =η×T _g ×ω _g =P _g.0 +η×T _g.0 ×Δω _g +η×ΔT _g ×ω _g.0 Δω _g =ω _g -ω _g.0 ΔT _g = T _g - T _g.0 Wherein, _Pg is the output power of the generator rotor of the wind turbine; η is the generator efficiency; _ωg is the angular velocity of the generator rotor; _Tg.0 is the initial electromagnetic torque of the generator rotor; _Δωg is the change in angular velocity of the generator rotor; _ΔTg is the change in electromagnetic torque of the generator rotor; _ωg.0 is the initial angular velocity of the generator rotor; The expression of the first-order inertia link of the pitch angle in the variable pitch model when the pitch angle variable is zero is: Wherein, β _ref is the pitch angle reference value, which is zero; is the first-order pitch angle derivative of the variable pitch model, wherein the variable pitch model is a first-order inertia link containing amplitude limitation and speed limitation; τ _β is the time constant of the first-order inertia link; β is the pitch angle; The first state space expression is: Wherein, a is the coefficient corresponding to the angular velocity of the wind turbine rotor, b is the coefficient corresponding to the pitch angle, c is the coefficient corresponding to the wind speed, and d is the constant term of the linear formula; ω _r is the angular velocity of the wind turbine rotor; is the derivative of the angular velocity of the fan rotor; ω _g is the angular velocity of the generator rotor; is the derivative of the angular velocity of the generator rotor; θ is the angular displacement difference between the fan rotor and the generator rotor; is the derivative of the angular displacement difference between the fan rotor and the generator rotor; is the derivative of φ, which is the difference between the angular velocity of the wind turbine rotor and the reference angular velocity of the wind turbine rotor; _V0 is the initial wind speed; _Jr is the moment of inertia of the wind turbine rotor; _Jg is the moment of inertia of the generator rotor of the wind turbine; _Ng is the gearbox speed ratio; A is the stiffness coefficient of the equivalent intermediate shaft; B is the damping coefficient of the equivalent intermediate shaft. 6. The method according to claim 2, characterized in that the relationship between the pitch angle derivative and the reference output power variation is: in, is the first-order pitch angle derivative of the variable pitch model, and the variable pitch model is a first-order inertia link with amplitude limitation and speed limitation; τ _β is the time constant of the first-order inertia link; β is the pitch angle; K _P is the proportional coefficient of the first-order inertia link; ω _r is the angular velocity of the fan rotor; K _I is the integral coefficient of the first-order inertia link; is the derivative of φ, which is the difference between the angular velocity of the wind turbine rotor and the reference angular velocity of the wind turbine rotor; K _W is the proportionality coefficient between the angular velocity of the wind turbine rotor and the output power; P _g,0 is the initial output power of the generator rotor of the wind turbine; ΔP _ref is the reference output power change of the generator rotor; The relationship between the output power and the initial output power is: Wherein, _Pg is the output power of the generator rotor of the wind turbine; η is the generator efficiency; _ωg is the angular velocity of the generator rotor; _Pg.0 is the initial output power of the generator rotor of the wind turbine; _ωg.0 is the initial angular velocity of the generator rotor; The relationship between the electromagnetic torque and the reference electromagnetic torque when the change of the electromagnetic torque is zero is expressed as: Where, _Tg is the electromagnetic torque of the generator rotor; is the derivative of the electromagnetic torque of the generator rotor; τ _g is the generator constant; T _g.0 is the initial electromagnetic torque of the generator rotor; ω _g.0 is the initial angular velocity of the generator rotor; The second state space expression is: Wherein, a is the coefficient corresponding to the angular velocity of the wind turbine rotor, b is the coefficient corresponding to the pitch angle, c is the coefficient corresponding to the wind speed, and d is the constant term of the linear formula; ω _r is the angular velocity of the wind turbine rotor; is the derivative of the angular velocity of the fan rotor; ω _g is the angular velocity of the generator rotor; is the derivative of the angular velocity of the generator rotor; θ is the angular displacement difference between the fan rotor and the generator rotor; is the derivative of the angular displacement difference between the fan rotor and the generator rotor; is the derivative of φ, which is the difference between the angular velocity of the wind turbine rotor and the reference angular velocity of the wind turbine rotor; _V0 is the initial wind speed; _Jr is the moment of inertia of the wind turbine rotor; _Jg is the moment of inertia of the generator rotor of the wind turbine; _Ng is the gearbox speed ratio; A is the stiffness coefficient of the equivalent intermediate shaft; B is the damping coefficient of the equivalent intermediate shaft. 7. A wind turbine primary frequency modulation simulation device, characterized in that the device comprises: An acquisition module, used for acquiring a reference output power variation for controlling a wind turbine generator to perform a frequency modulation; A construction module is used to construct a preset state space expression corresponding to the preset wind speed interval according to the relationship between the electromagnetic torque of the wind turbine and the reference electromagnetic torque in the preset wind speed interval, in combination with the double-mass model and the variable pitch model of the wind turbine, wherein the preset state space expression is used to characterize the relationship between the preset state variable of the wind turbine and the reference output power variation in the preset wind speed interval; A determination module, used to determine a target state space expression corresponding to the target wind speed interval according to the target wind speed interval to which the current wind speed belongs; A calculation module, used for substituting the reference output power variation into the target state space expression, calculating the preset state variable of the primary frequency modulation, so as to perform a primary frequency modulation simulation on the wind turbine; The preset wind speed interval includes a first preset interval and a second preset interval, the upper limit value of the first preset interval is equal to the lower limit value of the second preset interval, the preset state space expression includes a first state space expression corresponding to the first preset interval and a second state space expression corresponding to the second preset interval, the target wind speed interval is one of the first preset interval and the second preset interval, and the target state space expression is one of the first state space expression and the second state space expression. Wherein, when the preset wind speed interval is the first preset interval, the first state space expression is used to characterize the relationship between the preset state variable of the wind generator and the reference output power variation when only the electromagnetic torque of the wind generator is changed; When the preset wind speed interval is the second preset interval, the second state space expression is used to characterize the relationship between the preset state variable of the wind turbine and the reference output power variation when only the pitch angle of the wind turbine is changed. 8. An electronic device, characterized in that it comprises: a processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor and the memory communicate through the bus, and the machine-readable instructions are executed by the processor to execute the steps of the primary frequency modulation simulation method of a wind turbine as described in any one of claims 1 to 6. 9. A computer-readable storage medium, characterized in that a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the steps of the wind turbine primary frequency regulation simulation method according to any one of claims 1 to 6 are executed.