A method and system for acquiring low voltage ride through control parameter information

Abstract

This invention relates to a method and system for acquiring low-voltage ride-through control parameter information, belonging to the field of power system automation control technology. The method includes: receiving an acquisition request for low-voltage ride-through control parameter information; calculating an overvoltage peak value; calculating low-voltage ride-through control parameter information that meets preset conditions based on the overvoltage peak value; and outputting the low-voltage ride-through control parameter information. This method can automatically acquire and output the upper limit and range of values ​​for the low-voltage ride-through control parameters, exhibiting a high degree of automation and efficiency.

Description

Technical Field

[0001] This invention belongs to the field of power system automation control technology, and particularly relates to a method and system for obtaining low voltage ride-through control parameter information. Background Technology

[0002] When a short-circuit fault occurs in a large-scale renewable energy transmission system, temporary power frequency overvoltages can occur in the renewable energy collection areas at the sending end. In severe cases, this can lead to renewable energy disconnection from the grid, hindering renewable energy consumption. After an AC fault occurs, the grid voltage drops, and renewable energy enters low-voltage ride-through control. After the fault is cleared, due to voltage detection delays, the low-voltage ride-through characteristics of renewable energy cause reactive power surplus after voltage recovery, leading to overvoltage. Currently, most optimization suggestions for renewable energy fault ride-through control parameters and different control strategies are based on simulations and lack theoretical support.

[0003] Overall, there is currently a lack of a quantitative calculation method that considers overvoltage constraints for calculating the fault ride-through control parameters of new energy transmission systems under AC fault conditions. Summary of the Invention

[0004] The main objective of this invention is to overcome the shortcomings and deficiencies of the prior art and provide a method and system for acquiring low voltage ride-through control parameter information, which can automatically acquire and output the upper limit and range of low voltage ride-through control parameters, with a high degree of automation and high efficiency.

[0005] According to one aspect of the present invention, a method for obtaining low-voltage ride-through control parameter information is provided, the method comprising the following steps:

[0006] S1: Receive an acquisition request, the acquisition request being used to request the acquisition of low voltage ride-through control parameter information;

[0007] S2: Calculate the overvoltage peak value, and calculate the low voltage ride-through control parameter information that meets the preset conditions based on the overvoltage peak value;

[0008] S3: Output the low voltage ride-through control parameter information.

[0009] Preferably, the low-voltage ride-through control parameter is the equivalent reactive current coefficient of low-voltage ride-through control, the preset conditions include overvoltage constraint conditions and low-voltage ride-through requirements for new energy sources, and the low-voltage ride-through control parameter information includes the upper limit and range of the control parameter value.

[0010] Preferably, the calculation of the overvoltage peak value includes:

[0011] The formula for calculating the overvoltage peak value is:

[0012]

[0013] Among them, U r α is the peak value of the overvoltage at the new energy generator terminal, U is the infinite power supply potential, α is the equivalent reactive current coefficient reflecting the low voltage ride-through control, I0 is the steady-state current before the new energy fault, R is the equivalent resistance of the system, and X is the equivalent reactance of the system.

[0014] Preferably, the step of calculating the low-voltage ride-through control parameters that meet the preset conditions based on the overvoltage peak value includes:

[0015] Calculate the upper limit and range of the equivalent reactive current coefficient for overvoltage constraints, where the upper limit is:

[0016]

[0017] The range of values ​​is: α∈[0,α act );

[0018] In the formula, Z=R+jX, U act To protect the operating voltage.

[0019] Preferably, the step of calculating the low-voltage ride-through control parameters that meet the preset conditions based on the overvoltage peak value includes:

[0020] The range of values ​​for the equivalent reactive current coefficient that simultaneously satisfies the overvoltage constraint and the low-voltage ride-through requirement of new energy sources is calculated, and the reasonable range of values ​​for the equivalent reactive current coefficient is obtained as: α∈[1.05,α act ), where α act >1.05.

[0021] According to another aspect of the present invention, the present invention also provides a system for acquiring low voltage ride-through control parameter information, the system comprising:

[0022] The receiving module is used to receive an acquisition request, wherein the acquisition request is used to request the acquisition of low voltage ride-through control parameter information;

[0023] The calculation module is used to calculate the overvoltage peak value and, based on the overvoltage peak value, calculate the low voltage ride-through control parameter information that meets the preset conditions.

[0024] The output module is used to output the low voltage ride-through control parameter information.

[0025] Preferably, the low-voltage ride-through control parameter is the equivalent reactive current coefficient of low-voltage ride-through control, the preset conditions include overvoltage constraint conditions and low-voltage ride-through requirements for new energy sources, and the low-voltage ride-through control parameter information includes the upper limit and range of the control parameter value.

[0026] Preferably, the calculation module calculates the overvoltage peak value by:

[0027] The formula for calculating the overvoltage peak value is:

[0028]

[0029] Among them, U r α is the peak value of the overvoltage at the new energy generator terminal, U is the infinite power supply potential, α is the equivalent reactive current coefficient reflecting the low voltage ride-through control, I0 is the steady-state current before the new energy fault, R is the equivalent resistance of the system, and X is the equivalent reactance of the system.

[0030] Preferably, the calculation module calculates the low-voltage ride-through control parameter information that meets the preset conditions based on the overvoltage peak value, including:

[0031] Calculate the upper limit and range of the equivalent reactive current coefficient for overvoltage constraints, where the upper limit is:

[0032]

[0033] The range of values ​​is: α∈[0,α act );

[0034] In the formula, Z=R+jX, U act To protect the operating voltage.

[0035] Preferably, the calculation module calculates the low-voltage ride-through control parameter information that meets the preset conditions based on the overvoltage peak value, including:

[0036] The range of values ​​for the equivalent reactive current coefficient that simultaneously satisfies the overvoltage constraint and the low-voltage ride-through requirement of new energy sources is calculated, and the reasonable range of values ​​for the equivalent reactive current coefficient is obtained as: α∈[1.05,α act ), where α act >1.05.

[0037] Beneficial effects: This invention calculates the overvoltage peak value, calculates the low voltage ride-through control parameter information that meets the preset conditions based on the overvoltage peak value, and outputs the upper limit and range of the low voltage ride-through control parameter value. It has a high degree of automation and high efficiency.

[0038] The features and advantages of the present invention will become clear from the following accompanying drawings and a detailed description of specific embodiments thereof. Attached Figure Description

[0039] The accompanying drawings, which form part of this specification, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0040] Figure 1This is a flowchart of the method for obtaining low voltage ride-through control parameter information;

[0041] Figure 2 This is the simplified equivalent circuit of the new energy transmission grid in this invention;

[0042] Figure 3 This represents the vector relationship during the overvoltage stage in this invention.

[0043] Figures 4(a) and 4(b) show the relationship between αact, SCR, and X / R in this invention;

[0044] Figure 5 This refers to the new energy generator terminal voltage in the PSD-BPA simulation software of this invention.

[0045] Figure 6 This refers to the terminal voltage of the new energy generator in the PSCAD simulation software of this invention.

[0046] Figure 7 This is a schematic diagram of the system structure for acquiring low voltage ride-through control parameter information. Detailed Implementation

[0047] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0048] The following detailed description is exemplary and intended to provide further detailed explanation of the invention. Unless otherwise specified, all technical terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in this invention is for describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention.

[0049] Example 1

[0050] Figure 1 This is a flowchart illustrating the method for obtaining low-voltage ride-through control parameter information. For example... Figure 1 As shown, the present invention provides a method for obtaining low voltage ride-through control parameter information, the method comprising the following steps:

[0051] S1: Receive an acquisition request, the acquisition request being used to request the acquisition of low voltage ride-through control parameter information.

[0052] Specifically, the system receives a request from the user, triggers system startup, and after startup, it obtains the parameters required for calculation in order to perform subsequent calculations.

[0053] S2: Calculate the overvoltage peak value, and calculate the low voltage ride-through control parameter information that meets the preset conditions based on the overvoltage peak value.

[0054] Preferably, the low-voltage ride-through control parameter is the equivalent reactive current coefficient of low-voltage ride-through control, the preset conditions include overvoltage constraint conditions and low-voltage ride-through requirements for new energy sources, and the low-voltage ride-through control parameter information includes the upper limit and range of the control parameter value.

[0055] Preferably, the calculation of the overvoltage peak value includes:

[0056] The formula for calculating the overvoltage peak value is:

[0057]

[0058] Among them, U r α is the peak value of the overvoltage at the new energy generator terminal, U is the infinite power supply potential, α is the equivalent reactive current coefficient reflecting the low voltage ride-through control, I0 is the steady-state current before the new energy fault, R is the equivalent resistance of the system, and X is the equivalent reactance of the system.

[0059] Specifically, Figure 2 To simplify the equivalent new energy sending-end grid before and after a short-circuit fault by using a single-machine infinite bus system, U r Let U be the voltage at the power source terminal, and U be the infinite power source potential. r If the direction is the d-axis, and the d-axis leads the q-axis by 90 degrees, then the output current of the new energy source can be expressed as I = Iq. d +jI q I d For active current, I q For reactive current, θ I =tan -1 (I q / I d Z = R + jX is the Thevenin equivalent impedance from the new energy generator to the grid, let θ Z =tan -1 (X / R).

[0060] Depend on Figure 2 The circuit relationship allows us to obtain the terminal voltage of the new energy generator as follows:

[0061] U r =U+IZ (1)

[0062] The stages where overvoltage occurs include I. q =αI0, where α is the equivalent reactive current coefficient reflecting low-voltage ride-through control, I0 is the steady-state current before the new energy source fails, and I... d =0, θ I =90°, the equivalent potential U and system impedance Z are the same as before the fault. The vector relationship between voltage and current in this stage is as follows: Figure 3 As shown. The peak overvoltage at the new energy generator terminal is:

[0063]

[0064] Preferably, the step of calculating the low-voltage ride-through control parameters that meet the preset conditions based on the overvoltage peak value includes:

[0065] Calculate the upper limit and range of the equivalent reactive current coefficient for overvoltage constraints, where the upper limit is:

[0066]

[0067] The range of values ​​is: α∈[0,α act );

[0068] In the formula, Z=R+jX, U act To protect the operating voltage.

[0069] Specifically, the voltage at the new energy generator terminal reaches the protection trip voltage U. act When the voltage is typically 1.3 pu, it can cause the high-voltage grid disconnection of the new energy source, resulting in a voltage drop at the new energy source's generator terminal, U. r With the protection operating voltage U act The difference is

[0070] ΔU r (α)=U r (α)-U act (3)

[0071] There are also

[0072]

[0073] Since α < α0, ΔU r (α) is monotonically increasing in [0, α0), ΔU r The maximum value of (α) is

[0074]

[0075] ΔU r The minimum value of (α) is

[0076] ΔU r (0)=UU act <0 (6)

[0077] ΔU r The zero of (α) is

[0078]

[0079] Therefore, when α∈[0,α act When the fault is cleared, it will not cause the new energy high-voltage grid to disconnect from the grid, α∈[0,αact () represents the range of values ​​for the equivalent reactive current coefficient under overvoltage constraints.

[0080] Preferably, the step of calculating the low-voltage ride-through control parameters that meet the preset conditions based on the overvoltage peak value includes:

[0081] The range of values ​​for the equivalent reactive current coefficient that simultaneously satisfies the overvoltage constraint and the low-voltage ride-through requirement of new energy sources is calculated, and the reasonable range of values ​​for the equivalent reactive current coefficient is obtained as: α∈[1.05,α act ), where α act >1.05.

[0082] Specifically, further considering the requirements of my country's national standards for reactive current during low-voltage ride-through, a complete reasonable range for the equivalent reactive current coefficient is obtained. my country's national standards require that when the grid connection point voltage is 20% to 90% of the nominal voltage, the reactive current I injected into the wind farm system should be... q Should meet

[0083] I q ≥1.5×(0.9-U r )I N (8)

[0084] When the most severe fault occurs in the vicinity of the new energy source, i.e., U r =0.2pu, substituting the coefficients in equation (8), we obtain that the equivalent reactive current coefficient meeting the national standard requirements should be greater than 1.05. If α act If ≤1.05, then the equivalent reactive current coefficient that satisfies the low-voltage ride-through requirement cannot satisfy the overvoltage constraint; if α act If the value is greater than 1.05, then the reasonable range of values ​​for the equivalent reactive current coefficient is α∈[1.05, α...]. act ).

[0085] S3: Output the low voltage ride-through control parameter information.

[0086] Specifically, after calculating the low voltage ride-through control parameters, the calculation results can be represented by a 3D graph or contour map, or displayed on a monitor in the form of a text description.

[0087] This embodiment calculates the overvoltage peak value, calculates the low voltage ride-through control parameter information that meets the preset conditions based on the overvoltage peak value, and outputs the upper limit and range of the low voltage ride-through control parameter value, which has a high degree of automation and high efficiency.

[0088] For the common short-circuit ratio range of terminal voltage SCR∈[1.2,3] and impedance ratio range X / R∈[1,10] in engineering, α is calculated by equation (7). act . αact The relationship with SCR and X / R is plotted in Figure 4(a), with contour surfaces representing α. act The grid plane corresponds to α = 1.05. The three-dimensional region enclosed by the contour surface, the α = 1.05 grid plane, X / R = 1, and SCR = 3 represents a reasonable range of values ​​for simultaneously satisfying low-voltage ride-through requirements and overvoltage safety constraints under different systems. The α value in Figure 4(a) is... act Project the image onto the plane containing the SCR and X / R, and draw the contour map shown in Figure 4(b). The solid curve is α. act The contour lines corresponding to 1.05, and the regions formed by the solid curves and dashed lines for SCR and X / R values, indicate a reasonable range of equivalent reactive current coefficients α∈[1.05, α...]. act ).

[0089] Then, simulation verification is presented for the reasonable range of values ​​for the equivalent reactive current coefficient under the system parameters shown in Table 1. A simulation system was built using simulation software. Figure 2 The system is shown in Table 2. The new energy model for this system is a photovoltaic model, employing simplified calculations that do not consider the dynamic process of the DC-side capacitor. The AC fault is set to occur at 0.1s for a three-phase ground fault and clear at 0.19s. Simulations were performed with α = 0.2, 0.35, 0.8, 1.05, and 1.2 respectively. The simulation results of the new energy generator terminal voltage in the electromechanical software PSD-BPA are shown below. Figure 5 As shown, since the low voltage judgment time and the time constants of each control measurement are not zero, the new energy source is still under active and reactive power control during the low voltage ride-through period for a short time after the fault is cleared and the voltage is restored. The active and reactive currents of the new energy source remain at the values ​​during the low voltage ride-through period after the fault is cleared in the range of 0.19 to 0.21 seconds, which causes the voltage at the new energy source terminal to rise rapidly. Figure 5 The voltage spike between 0.19 and 0.2 s is caused by the simulation algorithm and calculation step size of PSD-BPA. Therefore, this invention uses the values ​​between 0.2 and 0.21 s as the simulation results. In this example, α... act =1.05, meaning that when the equivalent reactive current coefficient is less than 1.05, the high-voltage grid disconnection of new energy sources will not be triggered after the fault is cleared. Figure 5Simulation results show that when the equivalent reactive current coefficient α is set to its upper limit of 1.05, the overvoltage peak reaches 1.3 pu, which is the critical value corresponding to the protection setting. When the equivalent reactive current coefficient α is set to 1.2, the overvoltage peak exceeds 1.3 pu, and when the equivalent reactive current coefficient α is set to 0.2, 0.35, and 0.8, the voltage peak is below 1.3 pu, consistent with the calculated range of α values. Furthermore, the difference between the voltage at the new energy generator terminal and the protection setting increases with the increase of the equivalent reactive current coefficient α, consistent with the monotonicity observed in the analysis. Therefore, it can be concluded that the reasonable range of equivalent reactive current coefficient values ​​under overvoltage constraints in this example is α∈[0,1.05). When the voltage at the new energy generator terminal is within this range, it does not exceed 1.3 pu and will not trigger the high-voltage trip protection action. Because under severe fault conditions, the upper limit of the equivalent reactive current coefficient α... act This is equal to the minimum value of 1.05 required in the low voltage ride-through standard. Therefore, there is no reasonable range of equivalent reactive current coefficient values ​​in this example that simultaneously meets the overvoltage constraint and the low voltage ride-through standard. When designing low voltage ride-through for new energy sources, it is necessary to comprehensively consider the voltage support capability during the fault period and the voltage safety constraint after the fault is cleared.

[0090] Table 1 Simulation System Parameter Table

[0091]

[0092] Table 2 Photovoltaic Control Parameter Settings

[0093]

[0094] The same system was built in PSCAD, and the equivalent reactive current coefficient α was set to the upper limit of 1.05 for simulation verification. The simulation results of the new energy generator terminal voltage are as follows: Figure 6 As shown, the peak voltage at the new energy generator terminal, 1.31 pu, is quite close to the results of the electromechanical transient simulation.

[0095] Example 2

[0096] Figure 7 This is a schematic diagram of the system structure for acquiring low-voltage ride-through control parameter information. (Example:) Figure 7 As shown, the present invention also provides a system for acquiring low-voltage ride-through control parameter information, the system comprising:

[0097] The receiving module 701 is used to receive an acquisition request, wherein the acquisition request is used to request the acquisition of low voltage ride-through control parameter information;

[0098] Calculation module 702 is used to calculate the overvoltage peak value and calculate the low voltage ride-through control parameter information that meets the preset conditions based on the overvoltage peak value;

[0099] Output module 703 is used to output the low voltage ride-through control parameter information.

[0100] Preferably, the low-voltage ride-through control parameter is the equivalent reactive current coefficient of low-voltage ride-through control, the preset conditions include overvoltage constraint conditions and low-voltage ride-through requirements for new energy sources, and the low-voltage ride-through control parameter information includes the upper limit and range of the control parameter value.

[0101] Preferably, the calculation module 702 calculates the overvoltage peak value including:

[0102] The formula for calculating the overvoltage peak value is:

[0103]

[0104] Among them, U r α is the peak value of the overvoltage at the new energy generator terminal, U is the infinite power supply potential, α is the equivalent reactive current coefficient reflecting the low voltage ride-through control, I0 is the steady-state current before the new energy fault, R is the equivalent resistance of the system, and X is the equivalent reactance of the system.

[0105] Preferably, the calculation module 702 calculates the low-voltage ride-through control parameter information that meets the preset conditions based on the overvoltage peak value, including:

[0106] Calculate the upper limit and range of the equivalent reactive current coefficient for overvoltage constraints, where the upper limit is:

[0107]

[0108] The range of values ​​is: α∈[0,α act );

[0109] In the formula, Z=R+jX, U act To protect the operating voltage.

[0110] Preferably, the calculation module 702 calculates the low-voltage ride-through control parameter information that meets the preset conditions based on the overvoltage peak value, including:

[0111] The range of values ​​for the equivalent reactive current coefficient that simultaneously satisfies the overvoltage constraint and the low-voltage ride-through requirement of new energy sources is calculated, and the reasonable range of values ​​for the equivalent reactive current coefficient is obtained as: α∈[1.05,α act ), where α act >1.05.

[0112] The specific implementation process of the functions implemented by each module in this embodiment 2 is the same as the implementation process of each step in embodiment 1, and will not be repeated here.

[0113] 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.

[0114] 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.

[0115] 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.

[0116] 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.

[0117] 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 method for obtaining low-voltage ride-through control parameter information, characterized in that, The method includes the following steps: S1: Receive an acquisition request, the acquisition request being used to request the acquisition of low voltage ride-through control parameter information; S2: Calculate the overvoltage peak value, and calculate the low voltage ride-through control parameter information that meets the preset conditions based on the overvoltage peak value; S3: Output the low voltage ride-through control parameter information; The preset conditions include overvoltage constraint conditions and low-voltage ride-through requirements for new energy sources, and the low-voltage ride-through control parameter information includes the upper limit and range of the control parameter values. The calculation of the overvoltage peak value includes: The formula for calculating the overvoltage peak value is: in, U r This refers to the peak overvoltage at the new energy generator terminal. U The potential of the infinite power source α To reflect the equivalent reactive current coefficient of low voltage ride-through control, I 0 represents the steady-state current before the new energy source fails, R represents the system equivalent resistance, and X represents the system equivalent reactance. The low-voltage ride-through control parameter information calculated based on the overvoltage peak value to meet the preset conditions includes: Calculate the upper limit and range of the equivalent reactive current coefficient for overvoltage constraints, where the upper limit is: The range of values ​​is: α ∈[0, α act ); In the formula, Z=R+jX, U act To protect the operating voltage.

2. The method according to claim 1, characterized in that, The low-voltage ride-through control parameter information calculated based on the overvoltage peak value to meet the preset conditions includes: The range of values ​​for the equivalent reactive current coefficient that simultaneously satisfies the overvoltage constraint and the low-voltage ride-through requirement of new energy sources is calculated, and the reasonable range of values ​​for the equivalent reactive current coefficient is obtained as follows: α ∈[1.05, α act ) ,in α act >1.

05.

3. A system for acquiring low-voltage ride-through control parameter information, characterized in that, The system includes: The receiving module is used to receive an acquisition request, wherein the acquisition request is used to request the acquisition of low voltage ride-through control parameter information; The calculation module is used to calculate the overvoltage peak value and, based on the overvoltage peak value, calculate the low voltage ride-through control parameter information that meets the preset conditions. The output module is used to output the low voltage ride-through control parameter information; The low-voltage ride-through control parameter is the equivalent reactive current coefficient of low-voltage ride-through control. The preset conditions include overvoltage constraint conditions and low-voltage ride-through requirements for new energy sources. The low-voltage ride-through control parameter information includes the upper limit and range of the control parameter value. The calculation module calculates the overvoltage peak value, including: The formula for calculating the overvoltage peak value is: in, U r This refers to the peak overvoltage at the new energy generator terminal. U The potential of the infinite power source α To reflect the equivalent reactive current coefficient of low voltage ride-through control, I 0 represents the steady-state current before the new energy source fails, R represents the system equivalent resistance, and X represents the system equivalent reactance. The calculation module calculates low-voltage ride-through control parameter information that meets preset conditions based on the overvoltage peak value, including: Calculate the upper limit and range of the equivalent reactive current coefficient for overvoltage constraints, where the upper limit is: The range of values ​​is: α ∈[0, α act ); In the formula, Z=R+jX, U act To protect the operating voltage.

4. The system according to claim 3, characterized in that, The calculation module calculates low-voltage ride-through control parameter information that meets preset conditions based on the overvoltage peak value, including: The range of values ​​for the equivalent reactive current coefficient that simultaneously satisfies the overvoltage constraint and the low-voltage ride-through requirement of new energy sources is calculated, and the reasonable range of values ​​for the equivalent reactive current coefficient is obtained as follows: α ∈[1.05, α act ),in α act >1.05.

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