A wind farm simulation system and a simulation method thereof

Abstract

The present application relates to a kind of wind farm simulation system and its simulation method, wind farm simulation system includes: input module, wind farm signal module and wind farm grid interface module;Wherein, input module is used to input wind farm real-time operation data;Wind farm signal module is used to simulate the equivalent wind farm operating state switching and output according to wind farm real-time operation data;Wind farm grid interface module is used to establish the electrical connection between wind farm signal module and grid model.Utilize wind farm simulation system to do real-time simulation to wind farm.The technical scheme provided by the present application solves the problem that the difference of each wind turbine parameter cannot be reflected in the traditional modeling method, and by establishing the equivalent signal model of the same number of wind turbines as the actual wind farm, the wind farm simulation system can adapt to the actual wind farm control, solving the problem that the output performance of the current wind farm simulation system is only related to wind speed, and is independent of control influence, and cannot provide active support.

Description

Technical Field

[0001] This invention relates to the field of new energy access and control, specifically to a wind farm simulation system and simulation method. Background Technology

[0002] As wind power accounts for an increasingly larger share of the power system, its impact on the safe and stable operation of the power grid is growing, and the grid-source coordination capability of wind power is receiving more and more attention.

[0003] To study the grid-source interaction between wind farms and the power system, it is necessary to simulate wind farms. The basis for wind farm simulation is to establish an electrical equivalent model of the wind farm.

[0004] Since a wind farm consists of dozens or even hundreds of wind turbines, creating a detailed model for each turbine and considering factors such as electrical wiring involves a huge amount of modeling work and computation. Furthermore, ensuring the reliability of power flow and stability calculation algorithms is a significant challenge. Therefore, while meeting research objectives, pursuing realistic simulation of wind farm operation and efficient simulation has become a key research area in the field of wind farm technology.

[0005] Typically, modeling research focuses on the overall output characteristics of a wind farm. Therefore, current modeling methods often simplify the overall characteristics of a wind farm, ignoring the complex interactions between individual turbines within the farm. The research methods include: using an aggregation method to equate multiple wind turbine models with the same configuration and state to a single detailed turbine model, and using equivalent wind speeds to drive the corresponding turbine models; and using an equivalent method to establish a steady-state equivalent model of the wind farm based on the operating data of each wind turbine, by fitting the relationship between wind speed and output power, and outputting the corresponding power.

[0006] Traditional modeling methods treat wind farms as a whole, aiming to minimize the error between the wind farm's output and the actual active and reactive power. This approach ignores the dynamic characteristics of individual wind turbines within the wind farm, which may satisfy power flow and steady-state calculations. However, the grid connection performance of wind farms still largely depends on their power control systems. When grid frequency and voltage change, the wind farm's power control system can actively support the grid by adjusting active and reactive power. Current modeling methods cannot account for the parameter differences between individual wind turbines and are unsuitable for wind farm control systems, thus failing to achieve active support for the wind farm.

[0007] Therefore, the equivalent wind farm model obtained using traditional wind farm modeling methods cannot accurately and effectively simulate wind farms. Summary of the Invention

[0008] To address the shortcomings of existing technologies, the purpose of this invention is to provide a wind farm simulation system and its simulation method. This system solves the problem that traditional modeling methods cannot reflect the differences in parameters of each wind turbine. At the same time, by establishing an equivalent signal model of the number of wind turbines consistent with the actual wind farm, the wind farm simulation system can adapt to the actual wind farm control. This solves the problem that the output performance of current wind farm simulation systems is only related to wind speed, is detached from the influence of control, and cannot provide active support.

[0009] The objective of this invention is achieved through the following technical solution:

[0010] This invention provides a wind farm simulation system, which includes: an input module, a wind farm signal module, and a wind farm grid interface module;

[0011] The wind farm signal module includes: equivalent signal models of each wind turbine unit in the wind farm;

[0012] The wind farm grid interface module includes: a grid interface unit that is connected to the equivalent signal model of each wind turbine;

[0013] The input module is used to input real-time operating data of the wind farm;

[0014] The equivalent signal model is used to simulate the switching and output of the operating state of the equivalent wind turbine based on the real-time operating data of the wind farm.

[0015] The grid interface unit is used to convert the active and reactive power outputs of the equivalent signal model of the wind turbine into three-phase currents based on the effective voltage value of the grid model, and to establish an electrical connection between the equivalent signal model of the wind turbine and the grid model based on the three-phase currents.

[0016] Preferably, the real-time operating data includes, but is not limited to, wind speed and wind farm control commands.

[0017] Furthermore, the equivalent signal model of the wind turbine includes: a storage unit, a state switching unit, and an output unit;

[0018] The storage unit is used to store the fitting curve and key parameters of the wind turbine.

[0019] The state switching unit is used to switch the operating state of the simulated wind turbine based on wind farm control commands.

[0020] The output unit is used to simulate the current active power output, reactive power output, and other parameter operating values ​​of the wind turbine based on wind speed, the current operating status of the wind turbine, the fitted curve of the wind turbine, and key parameters.

[0021] This invention provides a wind farm simulation method based on a simulation system, the method comprising:

[0022] Obtain real-time operation data of wind farms;

[0023] By inputting real-time operating data of the wind farm into the wind farm simulation system, the operating values ​​of active power output, reactive power output and other parameters of each wind turbine in the wind farm are obtained through simulation.

[0024] The real-time operating data includes, but is not limited to, wind speed, wind farm control commands, and the effective voltage value of the power grid model;

[0025] Other parameters include, but are not limited to, pitch angle and rotational speed.

[0026] Compared with the closest existing technology, the present invention has the following advantages:

[0027] The technical solution provided by this invention includes: an input module, a wind farm signal module, and a wind farm grid interface module; the wind farm signal module includes: equivalent signal models of each wind turbine in the wind farm; the wind farm grid interface module includes: grid interface units respectively connected to the equivalent signal models of each wind turbine; wherein, the input module is used to input real-time operating data of the wind farm; the equivalent signal models are used to simulate the switching and output of the operating states of the equivalent wind turbines based on the real-time operating data of the wind farm; the grid interface units are used to convert the active and reactive power outputs of the equivalent signal models of the wind turbines into three-phase currents based on the effective voltage values ​​of the grid model, and to establish an electrical connection between the equivalent signal models of the wind turbines and the grid model based on the three-phase currents. This solution addresses the problem that traditional modeling methods cannot reflect the differences in parameters among wind turbine units. Furthermore, by establishing equivalent signal models for the same number of wind turbine units as in actual wind farms, the wind farm simulation system can adapt to actual wind farm control. This solves the problem that the output performance of current wind farm simulation systems is only related to wind speed, is detached from control influence, and cannot provide active support.

[0028] The technical solution provided by this invention can establish a wind farm simulation system according to the number of wind turbines in an actual wind farm. Due to the low complexity of the calculation module, it has high computational efficiency while meeting the research requirements on the interaction with the power grid.

[0029] The technical solution provided by this invention is applicable to real-time simulation, especially for hardware-in-the-loop simulation of controllers under the condition of considering the differences of wind turbine units.

[0030] The technical solution provided by this invention differs from the traditional grid interface between wind farms and power systems that uses effective value calculation mode or is only applicable to steady-state phasor mode. This invention, based on the grid interface provided by phase compensation, allows for asynchronous voltage acquisition and current calculation, without requiring synchronous operation of the grid model and the wind farm model. The established simulation system is an electromagnetic transient simulation system suitable for discrete solution. Attached Figure Description

[0031] Figure 1 This is a structural diagram of a wind farm simulation system;

[0032] Figure 2 This is a flowchart of a wind farm simulation method;

[0033] Figure 3 This is a schematic diagram of the connection structure between the wind farm simulation system and the power grid model;

[0034] Figure 4 This is a schematic diagram of the active power test results in an embodiment of the present invention;

[0035] Figure 5 This is a schematic diagram of the reactive power test results in an embodiment of the present invention. Detailed Implementation

[0036] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0037] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] Example 1:

[0039] This invention provides a wind farm simulation system, such as Figure 1 As shown, it includes: an input module, a wind farm signal module, and a wind farm grid interface module;

[0040] The wind farm signal module includes: equivalent signal models of each wind turbine unit in the wind farm;

[0041] The wind farm grid interface module includes: a grid interface unit that is connected to the equivalent signal model of each wind turbine;

[0042] The input module is used to input real-time operating data of the wind farm;

[0043] The equivalent signal model is used to simulate the switching and output of the operating state of the equivalent wind turbine based on the real-time operating data of the wind farm.

[0044] The grid interface unit is used to convert the active and reactive power outputs of the equivalent signal model of the wind turbine into three-phase currents based on the effective voltage value of the grid model, and to establish an electrical connection between the equivalent signal model of the wind turbine and the grid model based on the three-phase currents.

[0045] Specifically, the real-time operating data includes, but is not limited to, wind speed and wind farm control commands.

[0046] Furthermore, the equivalent signal model of the wind turbine includes: a storage unit, a state switching unit, and an output unit;

[0047] The storage unit is used to store the fitting curve and key parameters of the wind turbine.

[0048] The state switching unit is used to switch the operating state of the simulated wind turbine based on wind farm control commands.

[0049] The output unit is used to simulate the current active power output, reactive power output, and other parameter operating values ​​of the wind turbine based on wind speed, the current operating status of the wind turbine, the fitted curve of the wind turbine, and key parameters.

[0050] Furthermore, the switching of the simulated wind turbine operating state based on wind farm control commands in the state switching unit includes:

[0051] When no wind farm control command is received:

[0052] If the current operating status of the wind turbine is the start-up and grid-connected state and the current active power output and other parameters of the wind turbine have reached the preset threshold values ​​of the unrestricted power operating state, then the operating status of the wind turbine will be switched to the unrestricted power operating state.

[0053] If the current operating state of the wind turbine is in the inertial response control operating state, and the current active power output and other parameter values ​​of the wind turbine have all recovered to the values ​​when entering the inertial response control operating state, then the operating state of the wind turbine will switch to the power unconstrained operating state.

[0054] Otherwise, the operating status of the wind turbine will not be switched;

[0055] When a wind farm control command is received:

[0056] Determine if the wind farm control commands were issued incorrectly;

[0057] If so, the operating status of the wind turbine will not be switched; otherwise, the operating status of the wind turbine will be switched using wind farm control commands.

[0058] Furthermore, the determination of whether the wind farm control command was issued incorrectly includes:

[0059] When the wind farm control command is an active power control command or a reactive power control command:

[0060] If the wind turbine's normal operation flag C is 0, then the wind farm control command was issued incorrectly; otherwise, the wind farm control command was not issued incorrectly.

[0061] When the wind farm control command is a start-up control command:

[0062] If the wind turbine stop working flag D is 0, then the wind farm control command was issued incorrectly; otherwise, the wind farm control command was not issued incorrectly.

[0063] When the wind farm control command is a shutdown control command:

[0064] If the wind turbine stop working flag D is 1, then the wind farm control command was issued incorrectly; otherwise, the wind farm control command was not issued incorrectly.

[0065] Among them, the normal operation flag C of the wind turbine is 1 when the wind turbine is in the power unlimited operation state, power limited operation state, inertia response control operation state or reactive power control state, and 0 at other times.

[0066] The wind turbine stop working flag D is 1 when the wind turbine is not running, and 0 at other times.

[0067] Furthermore, the method of switching the operating state of wind turbine generators using wind farm control commands includes:

[0068] When the wind farm control command is a start-up control command, the operating status of the wind turbine unit is switched to the start-up control status.

[0069] When the wind farm control command is a shutdown control command:

[0070] If the value of the shutdown control command A is 0, the operating status of the wind turbine will switch to normal shutdown status.

[0071] If the value of the shutdown control command A is -1, the operating status of the wind turbine will switch to the fault shutdown status.

[0072] When the wind farm control command is an active power control command:

[0073] If the active power control command value is less than the current active power output of the wind turbine, the wind turbine's operating state will switch to power-limited operating state.

[0074] If the active power control command value is greater than or equal to the current active power output of the wind turbine and the inertia release flag B = 1, then the operating state of the wind turbine will switch to inertia response control operating state.

[0075] If the active power control command value is greater than or equal to the current active power output of the wind turbine and the inertia release flag B = 0, or if the active power control command value is equal to the current active power output of the wind turbine, then the operating state of the wind turbine will not switch.

[0076] When the wind farm control command is a reactive power control command:

[0077] If the reactive power control command value is not 0, the wind turbine's operating state will switch to reactive power control state.

[0078] Otherwise, the operating status of the wind turbine will not be switched.

[0079] Specifically, other parameters include, but are not limited to: pitch angle and rotational speed;

[0080] The wind turbine fitting curves stored in the storage unit include, but are not limited to: two-dimensional curves of wind speed-active power output, wind speed-pitch angle and wind speed-speed of the wind turbine when the wind turbine is connected to the grid and operating in an unconstrained power state.

[0081] And the two-dimensional curves of active power output versus speed and change in active power output versus change in pitch angle of wind turbine units when they are connected to the grid and operating under power-limited conditions;

[0082] The key parameters of the wind turbine stored in the storage unit include, but are not limited to:

[0083] When a wind turbine is running in the start-up state and the wind speed is high, the rate of change of the active power output, speed and pitch angle of the wind turbine is approximately the average value.

[0084] When the wind turbine is running in the start-up state and the wind speed is low, the rate of change of the active power output, speed, and pitch angle of the wind turbine is approximately the average value.

[0085] Wherein, the wind speed of the strong wind is above the rated wind speed, and the wind speed of the light wind is below the rated wind speed;

[0086] The fitting curves and key parameters of the wind turbine generator were obtained by fitting the historical operating data of the wind turbine generator.

[0087] Furthermore, the output unit simulates the current active power output, reactive power output, and other parameter operating values ​​of the wind turbine based on wind speed, the current operating status of the wind turbine, the fitted curve of the wind turbine, and key parameters, including:

[0088] When the current operating state of the wind turbine is an unconstrained power operating state:

[0089] By substituting wind speed into the two-dimensional curves of wind speed-active power, wind speed-pitch angle, and wind speed-speed of the wind turbine when it is connected to the grid and operating under unrestricted power conditions, the current active power output, pitch angle operating value, and speed operating value of the wind turbine can be obtained.

[0090] Substitute the current active power output of the wind turbine into the active-reactive power correspondence formula to obtain the current reactive power output of the wind turbine.

[0091] When the current operating state of the wind turbine is the start-up control state:

[0092] Get the wind speed type;

[0093] Substitute the approximate average rate of change of the wind turbine's rotational speed and the approximate average rate of change of the pitch angle into the first preset calculation formula to obtain the current operating values ​​of the wind turbine's rotational speed and pitch angle.

[0094] If the operating speed does not reach the grid-connected speed, then the current active and reactive output of the wind turbine is set to 0. Otherwise, the approximate average rate of change of the active output of the wind turbine corresponding to the wind speed type is substituted into the first preset calculation formula to obtain the current active output of the wind turbine.

[0095] Substitute the current active power output of the wind turbine into the active-reactive power correspondence formula to obtain the current reactive power output of the wind turbine.

[0096] When the current operating status of the wind turbine is normal shutdown:

[0097] Get the wind speed type;

[0098] If the current pitch angle of the wind turbine is not 90°, the approximate average rate of change of the pitch angle of the wind turbine corresponding to the wind speed type is substituted into the second preset calculation formula to obtain the current pitch angle operating value of the wind turbine; otherwise, the current pitch angle operating value of the wind turbine remains unchanged.

[0099] If the current speed of the wind turbine is not 0, the approximate average rate of change of the wind turbine's speed corresponding to the wind speed type is substituted into the second preset calculation formula to obtain the current operating value of the wind turbine's speed; otherwise, the current operating value of the wind turbine's speed is kept unchanged.

[0100] If the current speed of the wind turbine drops to the grid-connected speed, then the active and reactive power outputs of the wind turbine will be set to 0.

[0101] Otherwise, substitute the approximate average rate of change of the active power output of the wind turbine corresponding to the wind speed type into the second preset calculation formula to obtain the current active power output of the wind turbine.

[0102] Substitute the current active power output of the wind turbine into the active-reactive power correspondence formula to obtain the current reactive power output of the wind turbine.

[0103] When the current operating status of the wind turbine is a fault shutdown state:

[0104] Get the wind speed type;

[0105] If the pitch angle of the wind turbine does not reach 90°, the approximate average rate of change of the pitch angle of the wind turbine corresponding to the wind speed type is substituted into the third preset calculation formula to obtain the current pitch angle operating value of the wind turbine; otherwise, the current pitch angle operating value of the wind turbine remains unchanged.

[0106] If the wind turbine's rotational speed does not reach 0, the approximate average rate of change of the wind turbine's rotational speed corresponding to the wind speed type is substituted into the third preset calculation formula to obtain the current operating value of the wind turbine's rotational speed; otherwise, the current operating value of the wind turbine's rotational speed is kept unchanged.

[0107] Set the active and reactive power outputs of the wind turbine to 0;

[0108] When the wind turbine is currently operating in a power-limited state:

[0109] Get the wind speed type;

[0110] Substituting the active power command value into the two-dimensional curves of active power output - speed and active power output change - pitch angle change of the wind turbine when it is connected to the grid and operating under power-limited conditions, the target speed value and pitch angle change of the wind turbine are obtained. The sum of the current pitch angle and the pitch angle change of the wind turbine is taken as the target pitch angle value of the wind turbine.

[0111] If the pitch angle of the wind turbine does not reach the target value, the approximate average rate of change of the pitch angle of the wind turbine corresponding to the wind speed type is substituted into the second preset calculation formula to obtain the current pitch angle operating value of the wind turbine; otherwise, the current pitch angle operating value of the wind turbine remains unchanged.

[0112] If the wind turbine's rotational speed does not reach the target value, the approximate average rate of change of the wind turbine's rotational speed corresponding to the wind speed type is substituted into the second preset calculation formula to obtain the current operating value of the wind turbine's rotational speed; otherwise, the current operating value of the wind turbine's rotational speed is kept unchanged.

[0113] Substitute the active power command value into the delay stage to obtain the current active power output of the wind turbine, and substitute the current active power output of the wind turbine into the active-reactive power correspondence formula to obtain the current reactive power output of the wind turbine.

[0114] When the wind turbine is currently operating in inertial response control mode:

[0115] If the duration of entering the inertia response control operation state is less than the minimum value of the duration of the inertia release flag B and the maximum duration setting, then the approximate average value of the rate of change of the wind turbine speed corresponding to the wind speed type is substituted into the second preset calculation formula to obtain the current speed of the wind turbine.

[0116] Substitute the approximate average rate of change of the pitch angle of the wind turbine corresponding to the wind speed type into the first preset calculation formula to obtain the current pitch angle of the wind turbine.

[0117] The current active power output of the wind turbine is set to be the minimum value between the active power command value and the maximum active power limit value.

[0118] Substitute the current active power output of the wind turbine into the active-reactive power correspondence formula to obtain the current reactive power output of the wind turbine.

[0119] If the duration of entering the inertia response control operation state is equal to the minimum value between the duration of the inertia release flag B and the maximum duration setting, then the current active power output of the wind turbine will step to P. 1-low and P 1-low Substituting into the active-reactive power correspondence formula, we obtain the current reactive power output of the wind turbine.

[0120] The wind turbine's current speed and pitch angle should not jump abruptly.

[0121] If the duration of entering the inertia response control operation state is greater than the minimum value between the duration of the inertia release flag B and the maximum duration setting, then

[0122] Substitute the approximate average rate of change of the active power output of the wind turbine corresponding to the wind speed type into the first preset calculation formula to obtain the current active power output of the wind turbine until the current active power output of the wind turbine recovers to the value when entering the inertial response control operation state.

[0123] Substitute the current active power output of the wind turbine into the active-reactive power correspondence formula to obtain the current reactive power output of the wind turbine.

[0124] Substitute the approximate average rate of change of the wind turbine's rotational speed corresponding to the wind speed type into the first preset calculation formula to obtain the current operating value of the wind turbine's rotational speed, until the current operating value of the wind turbine's rotational speed is restored to the value when it enters the inertial response control operating state.

[0125] Substitute the approximate average rate of change of the pitch angle of the wind turbine corresponding to the wind speed type into the second preset calculation formula to obtain the current pitch angle operating value of the wind turbine until the current pitch angle operating value of the wind turbine is restored to the value when entering the inertial response control operating state.

[0126] When the current operating state of the wind turbine is reactive power control state:

[0127] The current active power output, pitch angle, and speed of the wind turbine remain unchanged;

[0128] If the reactive power command value is less than zero, then the current reactive power output of the wind turbine is set to the larger of the reactive power command value and the maximum reactive power limit.

[0129] If the reactive power command value is greater than zero, then the current reactive power output of the wind turbine is set to the smaller value between the reactive power command value and the maximum reactive power limit.

[0130] The maximum reactive power limit is obtained based on the current active power output of the wind turbine and the active-reactive power correspondence.

[0131] Wind types include strong winds and light winds;

[0132] P 1-low The preset power for the step point, the maximum duration setting value is preset during initial adjustment, and the duration of the inertia release flag B is given by the upper layer control.

[0133] Furthermore, the first preset calculation formula is:

[0134] X t =X t-1 +X k ·Δt

[0135] In the formula, X t X represents the current operating speed / pitch angle / active power output of the wind turbine. t-1 X represents the wind turbine's operating speed / pitch angle / active power output at the previous moment. k The approximate average rate of change of rotational speed / approximate average rate of change of pitch angle / approximate average rate of change of active power output of wind turbine corresponding to the current wind speed type, where Δt is the simulation step size;

[0136] The second preset calculation formula is:

[0137] X t =X t-1 -X k ·Δt

[0138] The third preset calculation formula is:

[0139] X t =X t-1 -2X k ·Δt

[0140] The active-reactive power correspondence is as follows:

[0141] Q = P·tan(arc(cosθ))

[0142] In the formula, cosθ is the power factor of the wind turbine, P is the active power output of the wind turbine, and Q is the reactive power output of the wind turbine corresponding to P / the maximum reactive power limit.

[0143] The P 1-low The formula for calculation is:

[0144]

[0145] In the formula, P low T is the power setting value corresponding to the maximum duration setting value. max T is the maximum duration setting. B The duration of the inertia release flag B.

[0146] Specifically, the calculation formula for the three-phase current converted from the active and reactive outputs of the wind turbine in the wind farm grid interface module is as follows:

[0147]

[0148] In the formula, θ A Let I be the phase angle of the A-phase current in the power grid model. rms I represents the effective value of the current in the power grid model. A Let I be the phase A current. B For phase B current, I c This refers to the C-phase current.

[0149] Wherein, the θ A The calculation formula is as follows:

[0150] θ A =θ ωt +arctan(Q / P)+2π*Δt / T

[0151] In the formula, P is the active power output of the equivalent signal model of the wind turbine, Q is the reactive power output of the equivalent signal model of the wind turbine, Δt is the simulation step size, T is the period of one voltage cycle in the power grid model, and θ ωt The phase angle of phase A voltage in the power grid model;

[0152] The I rms The calculation formula is as follows:

[0153]

[0154] In the formula, U rms This represents the effective voltage value in the power grid model.

[0155] The technical solution provided by this invention is based on wind turbine operation data. By using curve fitting and key parameter extraction, the wind turbine model is divided into several operating states. Each state is modeled separately. The switching between states is performed according to control commands to determine the final output of the wind turbine model.

[0156] The technical solution provided by this invention, under fixed-step simulation, can realize the electrical interface connection of the controlled current source model of the wind farm by using the phase-compensated grid interface based on active and reactive power and grid voltage phase-locking.

[0157] Example 2:

[0158] This invention provides a wind farm simulation method, such as... Figure 2 As shown, it includes:

[0159] Step 101: Obtain real-time operation data of the wind farm;

[0160] Step 102: Substitute the real-time operation data of the wind farm into the wind farm simulation system to simulate and obtain the active power output, reactive power output and other parameters of each wind turbine in the wind farm.

[0161] The real-time operating data includes, but is not limited to, wind speed, wind farm control commands, and the effective voltage value of the power grid model;

[0162] Other parameters include, but are not limited to, pitch angle and rotational speed.

[0163] Example 3:

[0164] To address the shortcomings of traditional wind farm simulation methods, such as the inability to reflect the parameter differences among wind turbines and the lack of adaptability to wind farm control systems, thus failing to provide active support, this invention provides a wind farm simulation system. During its establishment, this system creates equivalent signal models for each wind turbine based on its operational data. These models are electrically connected to the power grid model via a connected grid interface unit. This solves the problems of traditional modeling methods failing to reflect the parameter differences among wind turbines and the low modeling efficiency in creating detailed models for each wind turbine. Furthermore, by establishing an equivalent signal model for the same number of wind turbines as in actual wind farms, the system becomes adaptable to actual wind farm control, addressing the issue that current wind farm simulation systems' output performance is only related to wind speed, detached from control effects, and unable to provide active support.

[0165] The wind farm simulation system based on wind turbine operating data mainly consists of three parts: an input module, a wind farm signal module, and a wind farm-grid interface module. Wind turbine curve fitting and key parameter acquisition provide the data foundation for constructing the wind farm signal model. This simulation system can obtain the necessary output reference data for each wind turbine, including: active power, reactive power, pitch angle, speed, voltage, and RMS current. During simulation, the system needs to acquire wind turbine operating data (input from the input module). To obtain the necessary reference outputs, the inputs to the wind farm simulation system include wind speed, grid voltage, and control commands. The simulation system ultimately achieves electrical connection with the grid model. Using the proposed simulation system, it can satisfy the power flow calculation of the grid model under large-scale wind power participation, and also study the impact of complex grid conditions on the turbines based on the operating status of the wind turbines.

[0166] The specific construction process of this simulation system is as follows:

[0167] Step A: Obtain the fitting curve and key parameters of the wind turbine;

[0168] The fitted curves mentioned above include:

[0169] Two-dimensional curves of wind speed-active power, wind speed-pitch angle, and wind speed-speed when the wind turbine is connected to the grid and operating under unrestricted power conditions;

[0170] And the two-dimensional curves of active power versus speed and change in active power versus change in pitch angle of wind turbine units when they are connected to the grid and operating under power-limited conditions;

[0171] The key parameters mentioned above include:

[0172] When the wind turbine is running in the start-up state and the current wind speed is high, the rate of change of the active power, speed and pitch angle of the wind turbine is approximately the average value.

[0173] When a wind turbine is running in the start-up state and the current wind speed is light, the rate of change of the active power, speed, and pitch angle of the wind turbine is approximately the average value; wind speeds above the rated wind speed are considered strong winds, and wind speeds below the rated wind speed are considered light winds.

[0174] The process of obtaining the fitting curves and key parameters of the wind turbine is as follows:

[0175] By fitting the wind speed, active power, pitch angle, and speed of wind turbines operating in unrestricted power conditions in the historical database, two-dimensional curves of wind speed-active power, wind speed-pitch angle, and wind speed-speed of wind turbines operating in unrestricted power conditions in the grid are obtained.

[0176] By fitting the active power, speed, and pitch angle of wind turbines operating under power-limited conditions in the historical database, two-dimensional curves of active power versus speed and change in active power versus change in pitch angle of wind turbines operating under power-limited conditions in the grid-connected state are obtained.

[0177] The active power, speed, pitch angle and rotational speed of the wind turbine were calculated from the historical database when the wind turbine was running in the start-up state and the wind speed was high. The approximate average rate of change of the active power, speed and pitch angle of the wind turbine when the wind turbine was running in the start-up state and the current wind speed was high.

[0178] The active power, speed, pitch angle and rotational speed of the wind turbine were calculated from the historical database when the wind turbine was running in the start-up state and the wind speed was low. The approximate average rate of change of the active power, speed and pitch angle of the wind turbine when the wind turbine was running in the start-up state and the current wind speed was low was obtained.

[0179] Step B: Establish an equivalent signal model for the wind turbine based on historical operating data:

[0180] Step B-1: Construct storage units for storing the fitted curves and key parameters of the wind turbine generator;

[0181] Step B-2: Construct a state switching unit for simulating the switching of wind turbine operating states based on wind farm control commands;

[0182] When no wind farm control command is received:

[0183] If the current operating status of the wind turbine is the start-up and grid-connected state and the current active power output and other parameters of the wind turbine have reached the preset threshold values ​​of the unrestricted power operating state, then the operating status of the wind turbine will be switched to the unrestricted power operating state.

[0184] If the current operating state of the wind turbine is in the inertial response control operating state, and the current active power output and other parameter values ​​of the wind turbine have all recovered to the values ​​when entering the inertial response control operating state, then the operating state of the wind turbine will switch to the power unconstrained operating state.

[0185] Otherwise, the operating status of the wind turbine will not be switched;

[0186] When a wind farm control command is received:

[0187] Determine if the wind farm control commands were issued incorrectly;

[0188] If so, the operating status of the wind turbine will not be switched; otherwise, the operating status of the wind turbine will be switched using wind farm control commands.

[0189] The process of determining whether a wind farm control command has been issued incorrectly includes:

[0190] When the wind farm control command is an active power control command or a reactive power control command:

[0191] If the wind turbine's normal operation flag C is 0, then the wind farm control command was issued incorrectly; otherwise, the wind farm control command was not issued incorrectly.

[0192] When the wind farm control command is a start-up control command:

[0193] If the wind turbine stop working flag D is 0, then the wind farm control command was issued incorrectly; otherwise, the wind farm control command was not issued incorrectly.

[0194] When the wind farm control command is a shutdown control command:

[0195] If the wind turbine stop working flag D is 1, then the wind farm control command was issued incorrectly; otherwise, the wind farm control command was not issued incorrectly.

[0196] Note: The normal operation flag C of the wind turbine is 1 when the wind turbine is in the power unlimited operation state, power limited operation state, inertia response control operation state or reactive power control state, and 0 at other times.

[0197] The moment when the wind turbine stop working flag D is set to 1 is the moment when the wind turbine stops, and the moment when the wind turbine stop working flag D is set to 0 is the moment when the wind turbine starts.

[0198] The method of switching the operating state of wind turbine generators using wind farm control commands includes:

[0199] When the wind farm control command is a start-up control command, the operating status of the wind turbine unit is switched to the start-up control status.

[0200] When the wind farm control command is a shutdown control command:

[0201] If the value of the shutdown control command A is 0, the operating status of the wind turbine will switch to normal shutdown status.

[0202] If the value of the shutdown control command A is -1, the operating status of the wind turbine will switch to the fault shutdown status.

[0203] When the wind farm control command is an active power control command:

[0204] If the active power control command value is less than the current active power output of the wind turbine, the wind turbine's operating state will switch to power-limited operating state.

[0205] If the active power control command value is greater than or equal to the current active power output of the wind turbine and the inertia release flag B = 1, then the operating state of the wind turbine will switch to inertia response control operating state.

[0206] If the active power control command value is greater than or equal to the current active power output of the wind turbine and the inertia release flag B = 0, or if the active power control command value is equal to the current active power output of the wind turbine, then the operating state of the wind turbine will not switch.

[0207] When the wind farm control command is a reactive power control command:

[0208] If the reactive power control command value is not 0, the wind turbine's operating state will switch to reactive power control state.

[0209] Otherwise, the operating status of the wind turbine will not be switched.

[0210] Step B-3: Construct an output unit to simulate the current active power output, reactive power output, and other operating values ​​of the wind turbine based on wind speed, the current operating status of the wind turbine, the fitted curve of the wind turbine, and key parameters.

[0211] Unrestricted operation state: Based on the two-dimensional curves of wind speed-active power, wind speed-pitch angle and wind speed-speed of wind turbines when they are connected to the grid and operating in an unrestricted power state, the output of each wind turbine in this state, such as active power, reactive power, speed and pitch angle, is obtained according to the input wind speed.

[0212] Start-up control status: Pitch angle and speed output are uniformly calculated according to formula (1):

[0213] X t =X t-1 +X k ·Δt (1)

[0214] In the formula, X tX represents the current operating speed / pitch angle / active power output of the wind turbine. t-1 X represents the wind turbine's operating speed / pitch angle / active power output at the previous moment. k The approximate average rate of change of rotational speed / approximate average rate of change of pitch angle / approximate average rate of change of active power output of wind turbine corresponding to the current wind speed type, where Δt is the simulation step size;

[0215] When the rotational speed reaches the grid-connected speed, the active power gradually increases from the initial value of 0, and its output is calculated according to formula (1);

[0216] Once the rotational speed, pitch angle, and active power reach the threshold values ​​for unrestricted operation, they will remain unchanged, and at this time, flag C will be set to 1.

[0217] Normal shutdown state: Pitch angle, speed and active power output are calculated uniformly according to formula (2):

[0218] X t =X t-1 -X k ·Δt (2)

[0219] When the rotational speed reaches the grid-connected speed, the active power becomes 0. When the rotational speed and pitch angle values ​​change from 0 to 90 degrees respectively, they will remain unchanged. At this time, the normal operation status flag C will be set to 0.

[0220] Fault shutdown state: The active power becomes 0, and the pitch angle and speed values ​​are uniformly calculated according to formula (3) until the pitch angle and speed values ​​gradually recover to 90 and 0 respectively. At this time, the normal operation status flag C is set to 0.

[0221] X t =X t-1 -2X k ·Δt (3)

[0222] Power-limited operation mode: When the wind turbine is connected to the grid and is in a power-limited operation state, the two-dimensional curves of the active power of the wind turbine and the change in active power and the change in pitch angle are used to obtain the target value of the speed and the change in pitch angle. Based on the pitch angle at the current wind speed, the target value of the pitch angle is obtained.

[0223] The actual active power output value is obtained by passing the active power command P. cmd The input to the delay stage is obtained, and the actual output values ​​of speed and pitch angle are calculated according to formula (2). In the pitch angle calculation, the k value is taken as the rate of change corresponding to the rated wind speed. The speed and pitch angle remain unchanged after reaching the target value.

[0224] Inertia response control operation mode: If the duration is less than the minimum value between the duration of flag bit B and the maximum duration setting, the actual active power output is P. cmd The actual speed output is calculated according to formula (2) and the pitch angle output is calculated according to formula (1).

[0225] If the duration is equal to the minimum value between the duration of flag bit B and the maximum duration setting value.

[0226] Actual active power output P 1-low Calculate according to equation (4);

[0227]

[0228] In the formula, P low T is the power setting value corresponding to the maximum duration setting value. max T is the maximum duration setting value. B The duration of the inertia release flag B.

[0229] If the duration is greater than the minimum value between the duration of flag bit B and the maximum duration setting value.

[0230] The actual output of active power and speed is based on formula (1), and once the target value is reached, it will not change.

[0231] The actual output of the pitch angle is based on formula (2). Once the target value is reached, it no longer changes, and the inertia response control operation mode ends.

[0232] The target value is the output value before entering the inertia response control operation mode. The maximum duration setting value can be used as an initial adjustment setting to a specific value. Flag B, like A, is an external command, and the duration is entirely determined externally.

[0233] Reactive power control mode: When the reactive power command value Q cmd When the reactive power is less than zero, the actual output value of reactive power is Q. cmd The larger of the reactive power limit and the reactive power limit, when Q cmd When the value is greater than zero, the actual output value of reactive power is Q. cmd The smaller value between the reactive power limit and the reactive power command limit. The reactive power command limit is calculated based on the current active power and power factor, as shown in equation (5).

[0234] Q = P·tan(arc(cosθ)) (5)

[0235] In the formula, cosθ is the power factor of the wind turbine. Under normal operating conditions, cosθ = 1. The maximum and minimum values ​​of cosθ are generally ±0.95. When it reaches its maximum or minimum value, the corresponding maximum and minimum reactive power limits can be obtained. P is the active power output of the wind turbine, and Q is the reactive power output of the wind turbine corresponding to P / the maximum reactive power limit.

[0236] The active power, speed, and pitch angle remain unchanged.

[0237] Step B-4:

[0238] The storage unit and the state switching unit are connected to the output unit respectively to generate the equivalent signal model of the wind turbine.

[0239] Step C:

[0240] Following steps A and B, generate equivalent signal models for each wind turbine in the wind farm, and use these equivalent signal models to form a wind farm signal module.

[0241] Step D: Construct the input module;

[0242] The input module is used to collect operational data from the wind farm, including wind speed and wind farm control commands.

[0243] Step E: Construct a wind farm grid interface module, which includes: grid interface units that are connected to the equivalent signal models of each wind turbine;

[0244] The grid interface unit is used to convert the active and reactive power outputs of the equivalent signal model of the wind turbine into three-phase currents based on the effective voltage value of the grid model, and to establish an electrical connection between the equivalent signal model of the wind turbine and the grid model based on the three-phase currents.

[0245] Specifically, the active and reactive power outputs of the equivalent signal model of the wind turbine need to be converted into instantaneous three-phase currents through the grid interface before they can be electrically connected to the power system. The grid interface unit calculates the effective value based on the instantaneous three-phase voltage values ​​collected at the current moment using equation (6), obtains the phase angle using a phase-locked loop, and after phase compensation, uses a controlled current source to realize the three-phase instantaneous current output at the next moment. The effective value of the three-phase current can be calculated according to equation (7), and the phase angle of the A-phase current is calculated according to equation (8).

[0246]

[0247] In the formula, f represents the grid frequency, T represents the period of one cycle of the grid voltage, both f and T can be determined by a phase-locked loop, u(t) represents the instantaneous voltage value, and U rms This indicates the effective value of the voltage.

[0248]

[0249] θ A =θ ωt +arctan(Q / P)+2π*Δt / T (8)

[0250] In the formula I rms Represents the effective value of the current, θ A θ represents the phase angle of phase A. ωt The phase angle of the A-phase voltage locked by the phase-locked loop is represented by Q and P, which represent the reactive and active power of the wind farm model, respectively. The third term in the formula is the compensation phase.

[0251] The instantaneous values ​​of the three-phase currents are calculated by equation (9), and the electrical connection with the power grid is achieved by using a controlled current source.

[0252]

[0253] Step F: Connect the input module, wind farm signal module, and wind farm grid interface module in sequence to generate the wind farm simulation system. The connection structure diagram between the wind farm simulation system and the grid model is shown below. Figure 3 As shown.

[0254] Example 4:

[0255] A 2MW wind turbine equivalent signal model was built using Matlab, generating a 100MW wind farm simulation system with 50 wind turbines. This system was then applied to the RTLAB real-time simulation environment and integrated with the wind farm power control system. Control commands were sent from the control system's host computer to the simulation system, enabling functional testing of active and reactive power control. The active power test results are shown below. Figure 4 As shown, the reactive power test results are as follows: Figure 5 As shown.

[0256] As shown in the figure, the wind farm simulation system takes into account certain losses and inductive reactance, and can complete the corresponding functional tests according to the control commands. Due to the differences in parameters and wind speeds of each wind turbine, there is a certain delay between the actual active power and the command in active power control.

[0257] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0258] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0259] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0260] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0261] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A wind farm simulation system, characterized in that, The simulation system includes: an input module, a wind farm signal module, and a wind farm grid interface module; The wind farm signal module includes: equivalent signal models of each wind turbine unit in the wind farm; The wind farm grid interface module includes: a grid interface unit that is connected to the equivalent signal model of each wind turbine; The input module is used to input real-time operating data of the wind farm; The equivalent signal model is used to simulate the switching and output of the operating state of the equivalent wind turbine based on the real-time operating data of the wind farm. The grid interface unit is used to convert the active and reactive power outputs of the equivalent signal model of the wind turbine into three-phase currents based on the effective voltage value of the grid model, and to establish an electrical connection between the equivalent signal model of the wind turbine and the grid model based on the three-phase currents. The equivalent signal model of the wind turbine generator includes: an output unit; The output unit is used to simulate the current active power output, reactive power output and other parameter operating values ​​of the wind turbine based on wind speed, the current operating status of the wind turbine, the fitting curve of the wind turbine and key parameters. Other parameters include: pitch angle and rotational speed; Key parameters of wind turbines include: active power output, speed, and approximate average rate of change of pitch angle. When the wind turbine is currently operating in inertial response control mode: If the duration of entering the inertia response control operation state is less than the minimum value of the duration of the inertia release flag B and the maximum duration setting, then the approximate average value of the rate of change of the wind turbine speed corresponding to the wind speed type is substituted into the second preset calculation formula to obtain the current speed of the wind turbine. Substitute the approximate average rate of change of the pitch angle of the wind turbine corresponding to the wind speed type into the first preset calculation formula to obtain the current pitch angle of the wind turbine. The current active power output of the wind turbine is set to be the minimum value between the active power command value and the maximum active power limit value. Substitute the current active power output of the wind turbine into the active-reactive power correspondence formula to obtain the current reactive power output of the wind turbine. If the duration of entering the inertia response control operation state is equal to the minimum value between the duration of the inertia release flag B and the maximum duration setting, then the current active power output of the wind turbine will step to... and will Substituting into the active-reactive power correspondence formula, we obtain the current reactive power output of the wind turbine. The wind turbine's current speed and pitch angle should not jump abruptly. If the duration of entering the inertia response control operation state is greater than the minimum value between the duration of the inertia release flag B and the maximum duration setting, then Substitute the approximate average rate of change of the active power output of the wind turbine corresponding to the wind speed type into the first preset calculation formula to obtain the current active power output of the wind turbine until the current active power output of the wind turbine is restored to the value when entering the inertial response control operation state. Substitute the current active power output of the wind turbine into the active-reactive power correspondence formula to obtain the current reactive power output of the wind turbine. Substitute the approximate average rate of change of the wind turbine's rotational speed corresponding to the wind speed type into the first preset calculation formula to obtain the current operating value of the wind turbine's rotational speed, until the current operating value of the wind turbine's rotational speed is restored to the value when it enters the inertial response control operating state. Substitute the approximate average rate of change of the pitch angle of the wind turbine corresponding to the wind speed type into the second preset calculation formula to obtain the current pitch angle operating value of the wind turbine until the current pitch angle operating value of the wind turbine is restored to the value when entering the inertial response control operating state. The preset power for the step point, the maximum duration setting value is preset during initial adjustment, and the duration of the inertia release flag B is given by the upper layer control.

2. The simulation system as described in claim 1, characterized in that, The real-time operational data includes wind speed and wind farm control commands.

3. The simulation system as described in claim 2, characterized in that, The equivalent signal model of the wind turbine includes: a storage unit and a state switching unit; The storage unit is used to store the fitting curve and key parameters of the wind turbine. The state switching unit is used to switch the operating state of the wind turbine generator based on the simulation of wind farm control commands.

4. The simulation system as described in claim 3, characterized in that, The switching of wind turbine operating states based on wind farm control commands includes: When no wind farm control command is received: If the current operating status of the wind turbine is the start-up and grid-connected state and the current active power output and other parameters of the wind turbine have reached the preset threshold values ​​of the unrestricted power operating state, then the operating status of the wind turbine will be switched to the unrestricted power operating state. If the current operating state of the wind turbine is in the inertial response control operating state, and the current active power output and other parameter values ​​of the wind turbine have all recovered to the values ​​when entering the inertial response control operating state, then the operating state of the wind turbine will switch to the power unconstrained operating state. Otherwise, the operating status of the wind turbine will not be switched; When a wind farm control command is received: Determine if the wind farm control commands were issued incorrectly; If so, the operating status of the wind turbine will not be switched; otherwise, the operating status of the wind turbine will be switched using wind farm control commands.

5. The simulation system as described in claim 4, characterized in that, The determination of whether the wind farm control command was issued incorrectly includes: When the wind farm control command is an active power control command or a reactive power control command: If the wind turbine's normal operation flag C is 0, then the wind farm control command was issued incorrectly; otherwise, the wind farm control command was not issued incorrectly. When the wind farm control command is a start-up control command: If the wind turbine stop working flag D is 0, then the wind farm control command was issued incorrectly; otherwise, the wind farm control command was not issued incorrectly. When the wind farm control command is a shutdown control command: If the wind turbine stop working flag D is 1, then the wind farm control command was issued incorrectly; otherwise, the wind farm control command was not issued incorrectly. Among them, the normal operation flag C of the wind turbine is 1 when the wind turbine is in the power unlimited operation state, power limited operation state, inertia response control operation state or reactive power control state, and 0 at other times. The wind turbine stop working flag D is 1 when the wind turbine is not running, and 0 at other times.

6. The simulation system as described in claim 4, characterized in that, The method of switching the operating status of wind turbine generators using wind farm control commands includes: When the wind farm control command is a start-up control command, the operating status of the wind turbine unit is switched to the start-up control status. When the wind farm control command is a shutdown control command: If the value of the shutdown control command A is 0, the operating status of the wind turbine will switch to normal shutdown status. If the value of the shutdown control command A is -1, the operating status of the wind turbine will switch to the fault shutdown status. When the wind farm control command is an active power control command: If the active power control command value is less than the current active power output of the wind turbine, the wind turbine's operating state will switch to power-limited operating state. If the active power control command value is greater than or equal to the current active power output of the wind turbine and the inertia release flag B=1, then the operating state of the wind turbine will switch to inertia response control operating state. If the active power control command value is greater than or equal to the current active power output of the wind turbine and the inertia release flag B=0, or if the active power control command value is equal to the current active power output of the wind turbine, then the operating state of the wind turbine will not switch. When the wind farm control command is a reactive power control command: If the reactive power control command value is not 0, the wind turbine's operating state will switch to reactive power control state. Otherwise, the operating status of the wind turbine will not be switched.

7. The simulation system as described in claim 3, characterized in that, The fitting curves of the wind turbine include: two-dimensional curves of wind speed-active power output, wind speed-pitch angle, and wind speed-speed when the wind turbine is connected to the grid and operating under unrestricted power conditions. And the two-dimensional curves of active power output versus speed and change in active power output versus change in pitch angle of wind turbine units when they are connected to the grid and operating under power-limited conditions; Key parameters of wind turbine units include: When a wind turbine is running in the start-up state and the wind speed is high, the rate of change of the active power output, speed and pitch angle of the wind turbine is approximately the average value. When the wind turbine is running in the start-up state and the wind speed is low, the rate of change of the active power output, speed, and pitch angle of the wind turbine is approximately the average value. Wherein, the wind speed of the strong wind is above the rated wind speed, and the wind speed of the light wind is below the rated wind speed; The fitting curves and key parameters of the wind turbine generator were obtained by fitting the historical operating data of the wind turbine generator.

8. The simulation system as described in claim 7, characterized in that, The simulation, based on wind speed, the current operating status of the wind turbine, and the fitted curve and key parameters of the wind turbine, simulates the current active power output, reactive power output, and other parameter operating values ​​of the wind turbine, including: When the current operating state of the wind turbine is an unconstrained power operating state: By substituting wind speed into the two-dimensional curves of wind speed-active power, wind speed-pitch angle, and wind speed-speed of the wind turbine when it is connected to the grid and operating under unrestricted power conditions, the current active power output, pitch angle operating value, and speed operating value of the wind turbine can be obtained. Substitute the current active power output of the wind turbine into the active-reactive power correspondence formula to obtain the current reactive power output of the wind turbine. When the current operating state of the wind turbine is the start-up control state: Get the wind speed type; Substitute the approximate average rate of change of the wind turbine's rotational speed and the approximate average rate of change of the pitch angle into the first preset calculation formula to obtain the current operating values ​​of the wind turbine's rotational speed and pitch angle. If the operating speed does not reach the grid-connected speed, then the current active and reactive output of the wind turbine is set to 0. Otherwise, the approximate average rate of change of the active output of the wind turbine corresponding to the wind speed type is substituted into the first preset calculation formula to obtain the current active output of the wind turbine. Substitute the current active power output of the wind turbine into the active-reactive power correspondence formula to obtain the current reactive power output of the wind turbine. When the current operating status of the wind turbine is normal shutdown: Get the wind speed type; If the current pitch angle of the wind turbine is not 90°, the approximate average rate of change of the pitch angle of the wind turbine corresponding to the wind speed type is substituted into the second preset calculation formula to obtain the current pitch angle operating value of the wind turbine; otherwise, the current pitch angle operating value of the wind turbine remains unchanged. If the current speed of the wind turbine is not 0, the approximate average rate of change of the wind turbine's speed corresponding to the wind speed type is substituted into the second preset calculation formula to obtain the current operating value of the wind turbine's speed; otherwise, the current operating value of the wind turbine's speed is kept unchanged. If the current speed of the wind turbine drops to the grid-connected speed, then the active and reactive power outputs of the wind turbine will be set to 0. Otherwise, substitute the approximate average rate of change of the active power output of the wind turbine corresponding to the wind speed type into the second preset calculation formula to obtain the current active power output of the wind turbine. Substitute the current active power output of the wind turbine into the active-reactive power correspondence formula to obtain the current reactive power output of the wind turbine. When the current operating status of the wind turbine is a fault shutdown state: Get the wind speed type; If the pitch angle of the wind turbine does not reach 90°, the approximate average rate of change of the pitch angle of the wind turbine corresponding to the wind speed type is substituted into the third preset calculation formula to obtain the current pitch angle operating value of the wind turbine; otherwise, the current pitch angle operating value of the wind turbine remains unchanged. If the wind turbine's rotational speed does not reach 0, the approximate average rate of change of the wind turbine's rotational speed corresponding to the wind speed type is substituted into the third preset calculation formula to obtain the current operating value of the wind turbine's rotational speed; otherwise, the current operating value of the wind turbine's rotational speed is kept unchanged. Set the active and reactive power outputs of the wind turbine to 0; When the wind turbine is currently operating in a power-limited state: Get the wind speed type; Substituting the active power command value into the two-dimensional curves of active power output - speed and active power output change - pitch angle change of the wind turbine when it is connected to the grid and operating under power-limited conditions, the target speed value and pitch angle change of the wind turbine are obtained. The sum of the current pitch angle and the pitch angle change of the wind turbine is taken as the target pitch angle value of the wind turbine. If the pitch angle of the wind turbine does not reach the target value, the approximate average rate of change of the pitch angle of the wind turbine corresponding to the wind speed type is substituted into the second preset calculation formula to obtain the current pitch angle operating value of the wind turbine; otherwise, the current pitch angle operating value of the wind turbine remains unchanged. If the wind turbine's rotational speed does not reach the target value, the approximate average rate of change of the wind turbine's rotational speed corresponding to the wind speed type is substituted into the second preset calculation formula to obtain the current operating value of the wind turbine's rotational speed; otherwise, the current operating value of the wind turbine's rotational speed is kept unchanged. Substitute the active power command value into the delay stage to obtain the current active power output of the wind turbine, and substitute the current active power output of the wind turbine into the active-reactive power correspondence formula to obtain the current reactive power output of the wind turbine. When the current operating state of the wind turbine is reactive power control state: The current active power output, pitch angle, and speed of the wind turbine remain unchanged; If the reactive power command value is less than zero, then the current reactive power output of the wind turbine is set to the larger of the reactive power command value and the maximum reactive power limit. If the reactive power command value is greater than zero, then the current reactive power output of the wind turbine is set to the smaller value between the reactive power command value and the maximum reactive power limit. The maximum reactive power limit is obtained based on the current active power output of the wind turbine and the active-reactive power correspondence. Wind speed types include strong winds and light winds.

9. The simulation system as described in claim 8, characterized in that, The first preset calculation formula is: In the formula, This represents the current operating speed / pitch angle / active power output of the wind turbine. This represents the wind turbine's operating speed / pitch angle / active power output at the previous moment. This is the approximate average rate of change of rotational speed corresponding to the current wind speed type / approximate average rate of change of pitch angle / approximate average rate of change of active power output of the wind turbine. This is for simulating step size; The second preset calculation formula is: The third preset calculation formula is: The active-reactive power correspondence is as follows: In the formula, The power factor of the wind turbine. This refers to the active power output of the wind turbine. To and The corresponding reactive power output / maximum reactive power limit of the wind turbine unit; The The formula for calculation is: In the formula, The power setting value corresponding to the maximum duration setting. Set a value for the maximum duration. The duration of the inertia release flag B.

10. The simulation system as described in claim 1, characterized in that, The formulas for calculating the three-phase current converted from the active and reactive outputs of the wind turbine generator's equivalent signal model are as follows: In the formula, The phase angle of the A-phase current in the power grid model. The effective value of the current in the power grid model. This is the current in phase A. This is the B-phase current. This refers to the C-phase current. Among them, the The calculation formula is as follows: In the formula, The active power output of the equivalent signal model of the wind turbine generator. The reactive power output of the equivalent signal model of the wind turbine generator. For simulating step size, For the voltage cycle in the power grid model, The phase angle of phase A voltage in the power grid model; The The calculation formula is as follows: In the formula, This represents the effective voltage value in the power grid model.

11. A wind farm simulation method based on the simulation system according to any one of claims 1 to 10, characterized in that, The method includes: Obtain real-time operation data of wind farms; By inputting real-time operating data of the wind farm into the wind farm simulation system, the operating values ​​of active power output, reactive power output and other parameters of each wind turbine in the wind farm are obtained through simulation. The real-time operating data includes wind speed, wind farm control commands, and the effective voltage value of the power grid model; The other parameters include: pitch angle and rotational speed.

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