A method and system for calculating short-circuit ratio of multiple stations in a new energy cluster

Abstract

The present invention provides a method and system for calculating the short-circuit ratio of multiple stations in a new energy cluster, including: obtaining the current and voltage injected into the power grid by each new energy station; analyzing the voltage influence between each new energy station based on the current and voltage injected into the power grid by each new energy station to obtain the voltage interaction coefficient; calculating the short-circuit capacity of the machine-end bus of the new energy station based on the current and voltage injected into the power grid by each new energy station; calculating the short-circuit ratio of the new energy multi-station based on the voltage interaction coefficient and the machine-end bus short-circuit capacity combined with the new energy multi-station short-circuit ratio calculation formula. The present invention takes into account the mutual influence between each new energy station, so that the calculated short-circuit ratio is more accurate.

Description

Technical Field

[0001] The present invention relates to the field of renewable energy power generation technology and power systems, and in particular to a method and system for calculating short-circuit ratios of multiple stations in a renewable energy cluster. Background Art

[0002] The main development model of new energy is to gather multiple power stations such as wind power and photovoltaic power to boost the voltage and connect them to the grid. In areas where new energy is concentrated, conventional power sources are generally scarce, and voltage and frequency support is weak. Stability problems caused by large-scale new energy development are prominent, including transient overvoltage and wide-band oscillation. Studies have shown that the generation of these problems is closely related to the strength of the power grid at the point where the new energy is connected to the grid. The weaker the power grid strength, the greater the risk of stability problems such as overvoltage and oscillation.

[0003] The short-circuit ratio is an important indicator for measuring the strength of the power grid at the power / load access point. However, the conventional short-circuit ratio calculation method is mainly for a single device. For the scenario of new energy clusters being connected to the grid, only a single device is evaluated separately. The evaluation result is too optimistic and one-sided, resulting in low accuracy in measuring the true strength of the new energy unit grid connection point, which is easy to affect the planning and operation of the new energy cluster. Summary of the invention

[0004] In order to solve the problem that the existing technology mainly calculates the short-circuit ratio of a single device and only evaluates a single device separately, the evaluation result is too optimistic and one-sided, resulting in low accuracy in measuring the true strength of the grid connection point of the new energy unit, the present invention proposes a short-circuit ratio calculation method for a new energy cluster multi-station, including:

[0005] Obtain the current and voltage injected into the power grid by each new energy station;

[0006] Analyze the voltage impact between the renewable energy sites based on the current and voltage injected into the grid by the renewable energy sites to obtain the voltage interaction coefficient;

[0007] Calculate the terminal bus short-circuit capacity of each renewable energy station based on the current and voltage injected into the power grid by each renewable energy station;

[0008] The short-circuit ratio of the new energy multi-station is calculated based on the voltage interaction influence coefficient and the machine-end bus short-circuit capacity combined with the new energy multi-station short-circuit ratio calculation formula.

[0009] Preferably, the voltage impact between the renewable energy sites is analyzed based on the current and voltage injected into the power grid by the renewable energy sites to obtain the voltage interaction coefficient, including:

[0010] The power is calculated based on the current and voltage injected into the grid by the new energy injection station;

[0011] Based on the relationship between the mutual impedance between the two new energy stations, the self-impedance of the two new energy stations and the power, a ratio of the mutual impedance between the two new energy stations to the self-impedance of the two new energy stations is obtained;

[0012] Calculating the voltage ratio of the two new energy stations;

[0013] The voltage interaction coefficient is calculated from the ratio of the mutual impedance between the two new energy stations to the self-impedance of the two new energy stations and the voltage ratio.

[0014] Preferably, the voltage interaction coefficient is calculated as follows:

[0015]

[0016] In the formula, is the voltage interaction coefficient between new energy station l and new energy station i, is the self-impedance of the new energy station i, is the mutual impedance between the new energy station l and the new energy station i, is the voltage of the new energy station i, is the voltage of the new energy station l.

[0017] Preferably, the calculating the machine-end bus short-circuit capacity of each renewable energy station based on the current and voltage injected into the power grid by each renewable energy station includes:

[0018] Calculate the apparent power of each of the new energy sites based on the current and voltage injected into the power grid by each of the new energy sites when short-circuited;

[0019] The apparent power of each renewable energy station is used as the machine-end bus short-circuit capacity of each renewable energy station.

[0020] Preferably, the new energy multi-station short-circuit ratio calculation formula is as follows:

[0021]

[0022] Where P i +jQ i is the apparent power of the new energy station i, P i is the active power of the new energy station i, Q i is the reactive power of the new energy station i, P l +jQ l is the apparent power of the new energy station l, P l is the active power of the new energy station l, Q l is the reactive power of the new energy station l, is the voltage interaction coefficient between new energy station l and new energy station i, Ski is the short-circuit capacity of the busbar at the generator end of the new energy station i.

[0023] On the other hand, the present application also provides a new energy cluster multi-station short-circuit ratio calculation system, including:

[0024] An acquisition module is used to obtain the current and voltage injected into the power grid by each new energy station;

[0025] A coefficient calculation module, used to analyze the voltage impact between the renewable energy sites based on the current and voltage injected into the power grid by the renewable energy sites, and obtain the voltage interaction impact coefficient;

[0026] A capacity calculation module, used to calculate the machine-end bus short-circuit capacity of the new energy station based on the current and voltage injected into the power grid by each new energy station;

[0027] The short-circuit ratio calculation module is used to calculate the short-circuit ratio of the new energy multi-station based on the voltage interaction influence coefficient and the short-circuit capacity of the machine-end bus combined with the new energy multi-station short-circuit ratio calculation formula.

[0028] Preferably, the coefficient calculation module includes:

[0029] The impact current calculation submodule is used to calculate the power based on the current and voltage injected into the power grid by the new energy injection station;

[0030] a ratio calculation submodule, used for calculating the voltage ratio of the two new energy stations, and obtaining the ratio of the mutual impedance between the two new energy stations to the self-impedance of the two new energy stations from the relationship between the mutual impedance between the two new energy stations, the self-impedance of the two new energy stations and the power;

[0031] The influence coefficient calculation submodule is used to calculate the voltage interaction influence coefficient based on the ratio of the mutual impedance between the two new energy stations to the self-impedance of the two new energy stations and the voltage ratio.

[0032] Preferably, the influence coefficient calculation submodule calculates the voltage interaction influence coefficient by the following formula:

[0033]

[0034] In the formula, is the voltage interaction coefficient between new energy station l and new energy station i, is the self-impedance of the new energy station i, is the mutual impedance between the new energy station l and the new energy station i, is the voltage of the new energy station i, is the voltage of the new energy station l.

[0035] Preferably, the capacity calculation module includes:

[0036] An apparent power calculation submodule, used to calculate the apparent power of each of the new energy sites based on the current and voltage values ​​injected into the power grid by each of the new energy sites when short-circuited;

[0037] The short-circuit capacity determination submodule is used to use the apparent power of each of the renewable energy stations as the machine-end bus short-circuit capacity of each of the renewable energy stations.

[0038] Preferably, the short-circuit ratio calculation module calculates the short-circuit ratio of the new energy multi-station by the following formula:

[0039]

[0040] Where P i +jQ i is the apparent power of the new energy station i, P i is the active power of the new energy station i, Q i is the reactive power of the new energy station i, P l +jQ l is the apparent power of the new energy station l, P l is the active power of the new energy station l, Q l is the reactive power of the new energy station l, is the voltage interaction coefficient between new energy station l and new energy station i, S ki is the short-circuit capacity of the busbar at the generator end of the new energy station i.

[0041] In another aspect, the present application further provides a computing device, comprising: one or more processors;

[0042] a processor for executing one or more programs;

[0043] When the one or more programs are executed by the one or more processors, a method for calculating short-circuit ratio of multiple stations in a new energy cluster as described above is implemented.

[0044] On the other hand, the present application also provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed, a method for calculating the short-circuit ratio of multiple stations in a new energy cluster as described above is implemented.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] The present invention provides a method for calculating the short-circuit ratio of multiple stations in a new energy cluster, including: obtaining the current and voltage injected into the power grid by each new energy station; analyzing the voltage influence between each new energy station based on the current and voltage injected into the power grid by each new energy station to obtain the voltage interaction coefficient; calculating the machine-end bus short-circuit capacity of each new energy station based on the current and voltage injected into the power grid by each new energy station; calculating the new energy multi-station short-circuit ratio based on the voltage interaction coefficient and the machine-end bus short-circuit capacity combined with the new energy multi-station short-circuit ratio calculation formula. The present invention takes into account the mutual influence between each new energy station, so that the calculated short-circuit ratio is more accurate and can reflect the real strength of the new energy unit grid connection point. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 This is a flow chart of a method for calculating short-circuit ratio of multiple stations in a new energy cluster according to the present invention;

[0048] Figure 2 The short-circuit ratio calculation process of multiple new energy stations provided by the present invention;

[0049] Figure 3 This is a schematic diagram of the new energy multi-station coupling method provided by the present invention. DETAILED DESCRIPTION

[0050] The present invention proposes a method for calculating the short-circuit ratio of multiple stations in a new energy cluster, and provides a more accurate grid strength evaluation method for areas with a high proportion of new energy access, including the actual grid connection point strength of each new energy power station and the overall strength index of the entire cluster. It accurately evaluates the actual grid connection point strength index of each new energy power station under the cluster grid connection conditions, and scientifically guides the development planning and scheduling operation of new energy bases.

[0051] Embodiment 1:

[0052] A method for calculating short-circuit ratio of multiple stations in a new energy cluster, such as Figure 1 As shown, including:

[0053] Step 1: Obtain the current and voltage injected into the grid by each new energy station;

[0054] Step 2: Analyze the voltage impact between the renewable energy sites based on the current and voltage injected into the grid by the renewable energy sites to obtain the voltage interaction coefficient;

[0055] Step 3: Calculate the machine-end bus short-circuit capacity of each renewable energy station based on the current and voltage injected into the power grid by each renewable energy station;

[0056] Step 4: Calculate the new energy multi-station short-circuit ratio based on the voltage interaction influence coefficient and the machine-end target short-circuit capacity combined with the new energy multi-station short-circuit ratio calculation formula.

[0057] The present invention proposes a method for calculating the short-circuit ratio of multiple stations in a new energy cluster. The specific process is as follows: Figure 2 Shown include:

[0058] Step 1: Obtain the current and voltage injected into the grid by each renewable energy station. In the specific implementation process, obtain the current and voltage injected into the grid by each renewable energy station when short-circuited;

[0059] Link 1: Quoting the classic definition, the short-circuit ratio SCR for evaluating the strength of the power grid is defined as the ratio of the short-circuit capacity of the busbar at the new energy generator end to the rated power:

[0060]

[0061] Among them, S k The short-circuit capacity of the busbar at the generator end of the renewable energy power generation is obtained by calculating the short-circuit current of the power grid; S n It is the rated capacity of renewable energy power generation.

[0062] In step 2, the voltage impact between the renewable energy stations is analyzed based on the current and voltage injected into the grid by the renewable energy stations to obtain the voltage interaction coefficient, which specifically includes:

[0063] Link 2: In a new energy multi-station containing n new energy stations, the current injected into the grid by each new energy power generation is I1, I2, ..., I n Here, each new energy station is regarded as a node, each node is numbered, and the node impedance matrix Z is obtained from the voltage and current at each node, as shown in Figure 3 As shown, the voltage of the lth new energy station to the ith new energy station and power The impacts are:

[0064]

[0065]

[0066] In the formula, is the self-impedance of node i, i.e., the i-th row and i-th column of the node impedance matrix Z viewed from the busbar at the node i, in complex form; The impact of the current injected by the new energy source l on the voltage of node i; The current injected into the new energy source l; is the mutual impedance between node l and node i, that is, the i-th row and l-th column of the node impedance matrix Z viewed from the busbar end of the new energy i machine; The current injected by new energy source j is equivalent to the current at node i; The current injected by the new energy station l is equivalent to the power of the node i; is the voltage of node i; for The complex conjugate of ; for The complex conjugate of ; is the voltage at node l, is the apparent power of new energy source j, i and l are the serial numbers of the objects to be analyzed, and j is the ordinal part of the complex number.

[0067] In step 3, the machine-end bus short-circuit capacity of the new energy station is calculated based on the current and voltage injected into the power grid by each new energy station, specifically including:

[0068] Calculate the active power and reactive power of each object to be analyzed based on the current and voltage injected into the power grid by each object to be analyzed when short-circuited, and the phase difference between the injected voltage and current;

[0069] Calculate the apparent power of each object to be analyzed based on the current and voltage injected into the power grid when each object to be analyzed is short-circuited;

[0070] The apparent power of each object to be analyzed is used as the machine-end bus short-circuit capacity of each object to be analyzed.

[0071] The step 4 of calculating the short-circuit ratio of the new energy multi-station based on the voltage interaction influence coefficient and the target short-circuit capacity of the generator end in combination with the short-circuit ratio calculation formula of the new energy multi-station specifically includes:

[0072] Step 3: Define the calculation method of short-circuit ratio of new energy multi-stations:

[0073]

[0074] In the formula, is the apparent power of node i, where P i is the active power of node i, Q i is the reactive power of node i, is the apparent power of node l, where P l is the active power of node l, Q l is the reactive power of node l, is the voltage interaction coefficient between node l and node i, which can be obtained according to formula (5):

[0075]

[0076] In the formula, is the self-impedance of node i, is the mutual impedance between node l and node i.

[0077] Step 4: Calculation process of short-circuit ratio of new energy multi-station:

[0078] Also include before step 1:

[0079] 1) Power flow calculation;

[0080] Based on the power grid data, power flow calculations are carried out to obtain basic power flow results including active power, reactive power, node voltage, etc. of new energy stations.

[0081] 2) Determine the calculation scope: synchronous power grid;

[0082] In 1), the power grid connected by AC lines is set as a synchronous power grid; the power grid connected by DC lines is set as an asynchronous power grid.

[0083] 3) Determine the calculation object and synchronize all new energy stations in the power grid;

[0084] In step 2, based on the current and voltage injected into the grid by each renewable energy station, the influence of voltage and power between each renewable energy station is analyzed to obtain the voltage interaction influence coefficient, which specifically includes:

[0085] 4) Calculation of voltage interaction coefficient: Calculate the voltage interaction coefficient according to formula (5).

[0086] The step 3 of calculating the short-circuit capacity of the busbar at the machine end of each renewable energy station based on the current and voltage injected into the power grid by each renewable energy station specifically includes:

[0087] 5) Short-circuit capacity calculation: Calculate the short-circuit capacity of the busbar at the generator end of each calculation object (new energy station) in 3);

[0088] Based on the power flow calculation, short-circuit current calculation is carried out, and the short-circuit current capacity of the busbar at the machine end of each calculation object is obtained.

[0089] The step 4 of calculating the short-circuit ratio of the new energy multi-station based on the voltage interaction influence coefficient and the target short-circuit capacity of the generator end in combination with the short-circuit ratio calculation formula of the new energy multi-station specifically includes:

[0090] 6) Calculate the short-circuit ratio of multiple renewable energy stations: Calculate the short-circuit ratio of multiple renewable energy stations according to formula (4).

[0091] The present invention takes into account the voltage interaction coefficient between new energy stations. Compared with the prior art in which the short-circuit ratio is calculated for only a single device, the result obtained is closer to reality and more accurate.

[0092] Embodiment 2:

[0093] A method for calculating short-circuit ratio of multiple stations in a new energy cluster, comprising:

[0094] (1) Define the calculation method of short-circuit ratio of multiple new energy stations:

[0095] Define the calculation method of short-circuit ratio of multiple new energy stations, including:

[0096] Link 1-1: Calculation method of short-circuit ratio of new energy multi-station:

[0097]

[0098] Where P i +jQ i is the apparent power of the new energy station i, P l +jQ l is the apparent power of the new energy station l;

[0099] Step 1-2: Definition is the voltage interaction coefficient between node l and node i:

[0100]

[0101] In the formula, is the self-impedance of node i, is the mutual impedance between node l and node i.

[0102] (2) Set up the short-circuit ratio calculation process for new energy multiple stations, including:

[0103] Step 2-1: Power flow calculation;

[0104] Step 2-2: Determine the calculation scope;

[0105] Step 2-3: Determine the calculation object, and calculate all new energy stations within the scope;

[0106] Step 2-4: Calculation of short-circuit capacity;

[0107] Step 2-5: Calculate the voltage interaction coefficient;

[0108] Step 2-6: Calculate the short-circuit ratio of multiple renewable energy stations.

[0109] Embodiment 3:

[0110] The present invention based on the same inventive concept also provides a new energy cluster multi-station short-circuit ratio calculation system, comprising:

[0111] An acquisition module is used to obtain the current and voltage injected into the power grid by each new energy station;

[0112] A coefficient calculation module, used to analyze the voltage impact between the renewable energy sites based on the current and voltage injected into the power grid by the renewable energy sites, and obtain the voltage interaction impact coefficient;

[0113] A capacity calculation module, used to calculate the machine-end bus short-circuit capacity of each renewable energy station based on the current and voltage injected into the power grid by each renewable energy station;

[0114] The short-circuit ratio calculation module is used to calculate the short-circuit ratio of the new energy multi-station based on the voltage interaction influence coefficient and the short-circuit capacity of the machine-end bus combined with the new energy multi-station short-circuit ratio calculation formula.

[0115] Coefficient calculation module, including:

[0116] The impact current calculation submodule is used to calculate the power based on the current and voltage injected into the power grid by the new energy injection station;

[0117] a ratio calculation submodule, used for calculating the voltage ratio of the two new energy stations, and obtaining the ratio of the mutual impedance between the two new energy stations to the self-impedance of the two new energy stations from the relationship between the mutual impedance between the two new energy stations, the self-impedance of the two new energy stations and the power;

[0118] The influence coefficient calculation submodule is used to calculate the voltage interaction influence coefficient based on the ratio of the mutual impedance between the two new energy stations to the self-impedance of the two new energy stations and the voltage ratio.

[0119] The influence coefficient calculation submodule calculates the voltage interaction influence coefficient by the following formula:

[0120]

[0121] In the formula, is the voltage interaction coefficient between new energy station l and new energy station i, is the self-impedance of the new energy station i, is the mutual impedance between the new energy station l and the new energy station i, is the voltage of the new energy station i, is the voltage of the new energy station l.

[0122] Capacity calculation module, including:

[0123] An apparent power calculation submodule, used to calculate the apparent power of each of the new energy sites based on the current and voltage values ​​injected into the power grid by each of the new energy sites when short-circuited;

[0124] The short-circuit capacity determination submodule is used to use the apparent power of each of the renewable energy stations as the machine-end bus short-circuit capacity of each of the renewable energy stations.

[0125] The short-circuit ratio calculation module calculates the short-circuit ratio of multiple renewable energy stations using the following formula:

[0126]

[0127] Where P i +jQ i is the apparent power of the new energy station i, P i is the active power of the new energy station i, Q i is the reactive power of the new energy station i, P l +jQ l is the apparent power of the new energy station l, P l is the active power of the new energy station l, Q l is the reactive power of the new energy station l, is the voltage interaction coefficient between new energy station l and new energy station i, S ki is the short-circuit capacity of the busbar at the generator end of the new energy station i.

[0128] For the convenience of description, the above parts of the device are divided into modules or units according to their functions and described separately. Of course, when implementing the present application, the functions of each module or unit can be implemented in the same or multiple software or hardware.

[0129] Based on the same inventive concept, in another embodiment of the present invention, a computing device is provided, the computing device including a processor and a memory, the memory is used to store a computer program, the computer program includes program instructions, and the processor is used to execute the program instructions stored in the computer storage medium. The processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc., which are the computing core and control core of the terminal, which are suitable for implementing one or more instructions, and are specifically suitable for loading and executing one or more instructions in a computer storage medium to implement the corresponding method flow or corresponding function; the processor described in the embodiment of the present invention can be used to execute the steps of a method for calculating the short-circuit ratio of multiple stations in a new energy cluster.

[0130] Based on the same inventive concept, in another embodiment of the present invention, the present invention also provides a storage medium, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device for storing programs and data. It is understandable that the computer-readable storage medium here can include both a built-in storage medium in a computer device and an extended storage medium supported by the computer device. The computer-readable storage medium provides a storage space, which stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by a processor are also stored in the storage space, and these instructions can be one or more computer programs (including program codes). It should be noted that the computer-readable storage medium here can be a high-speed RAM memory or a non-volatile memory, such as at least one disk memory. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the corresponding steps of a method for calculating the short-circuit ratio of a new energy cluster multi-station in the above embodiment.

[0131] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented 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.

[0132] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0133] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0134] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0135] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are included in the scope of the claims of the present invention to be approved.

Claims

1. A method for calculating short-circuit ratio of multiple stations in a new energy cluster, characterized in that: include: Obtain the current and voltage injected into the power grid by each new energy station; Analyze the voltage impact between the renewable energy sites based on the current and voltage injected into the grid by the renewable energy sites to obtain the voltage interaction coefficient; Calculate the terminal bus short-circuit capacity of each renewable energy station based on the current and voltage injected into the power grid by each renewable energy station; Calculate the short-circuit ratio of the new energy multi-station based on the voltage interaction influence coefficient and the short-circuit capacity of the machine-end bus combined with the short-circuit ratio calculation formula of the new energy multi-station; The calculation formula for the short-circuit ratio of new energy multi-stations is as follows: ； In the formula, is the short-circuit ratio of multiple renewable energy stations, For new energy stations i The apparent power, For new energy stations i The active power, For new energy stations i The reactive power, For new energy stations l The apparent power, For new energy stations l The active power, For new energy stations l The reactive power, For new energy stations l and new energy stations i The voltage interaction coefficient between For new energy stations i The short-circuit capacity of the machine-end busbar.

2. The method according to claim 1, characterized in that The voltage impact between the renewable energy sites is analyzed based on the current and voltage injected into the power grid by the renewable energy sites to obtain the voltage interaction coefficient, including: The power is calculated based on the current and voltage injected into the grid by the new energy injection station; Based on the relationship between the mutual impedance between the two new energy stations, the self-impedance of the two new energy stations and the power, a ratio of the mutual impedance between the two new energy stations to the self-impedance of the two new energy stations is obtained; Calculating the voltage ratio of the two new energy stations; The voltage interaction coefficient is calculated from the ratio of the mutual impedance between the two new energy stations to the self-impedance of the two new energy stations and the voltage ratio.

3. The method according to claim 2, characterized in that The voltage interaction coefficient is calculated as follows: ； In the formula, For new energy stations l and new energy stations i The voltage interaction coefficient between For new energy stations i The self-impedance, For new energy stations l With new energy stations i The mutual impedance between For new energy stations i The voltage, For new energy stations voltage.

4. The method according to claim 1, characterized in that The calculating the machine-end bus short-circuit capacity of each renewable energy station based on the current and voltage injected into the power grid by each renewable energy station comprises: Calculate the apparent power of each of the new energy sites based on the current and voltage injected into the power grid by each of the new energy sites when short-circuited; The apparent power of each renewable energy station is used as the machine-end bus short-circuit capacity of each renewable energy station.

5. A new energy cluster multi-station short-circuit ratio calculation system, characterized in that: include: An acquisition module is used to obtain the current and voltage injected into the power grid by each new energy station; A coefficient calculation module, used to analyze the voltage impact between the renewable energy sites based on the current and voltage injected into the power grid by the renewable energy sites, and obtain the voltage interaction impact coefficient; A capacity calculation module, used to calculate the machine-end bus short-circuit capacity of each renewable energy station based on the current and voltage injected into the power grid by each renewable energy station; A short circuit ratio calculation module, used to calculate the short circuit ratio of the new energy multi-station based on the voltage interaction influence coefficient and the short circuit capacity of the machine-end bus combined with a new energy multi-station short circuit ratio calculation formula; The short-circuit ratio calculation module calculates the short-circuit ratio of the new energy multi-station by the following formula: ； In the formula, is the short-circuit ratio of multiple renewable energy stations, For new energy stations i The apparent power, For new energy stations i The active power, For new energy stations i The reactive power, For new energy stations l The apparent power, For new energy stations l The active power, For new energy stations l The reactive power, For new energy stations l and new energy stations i The voltage interaction coefficient between For new energy stations i The short-circuit capacity of the machine-end busbar.

6. The system according to claim 5, characterized in that The coefficient calculation module comprises: The impact current calculation submodule is used to calculate the power based on the current and voltage injected into the power grid by the new energy injection station; a ratio calculation submodule, used for calculating the voltage ratio of the two new energy stations, and obtaining the ratio of the mutual impedance between the two new energy stations to the self-impedance of the two new energy stations from the relationship between the mutual impedance between the two new energy stations, the self-impedance of the two new energy stations and the power; The influence coefficient calculation submodule is used to calculate the voltage interaction influence coefficient based on the ratio of the mutual impedance between the two new energy stations to the self-impedance of the two new energy stations and the voltage ratio.

7. The system according to claim 6, characterized in that The influence coefficient calculation submodule calculates the voltage interaction influence coefficient by the following formula: ； In the formula, For new energy stations l and new energy stations i The voltage interaction coefficient between For new energy stations i The self-impedance, For new energy stations With new energy stations i The mutual impedance between For new energy stations i The voltage, For new energy stations voltage.

8. The system according to claim 5, characterized in that The capacity calculation module includes: An apparent power calculation submodule, used to calculate the apparent power of each of the new energy sites based on the current and voltage values ​​injected into the power grid by each of the new energy sites when short-circuited; The short-circuit capacity determination submodule is used to use the apparent power of each of the renewable energy stations as the machine-end bus short-circuit capacity of each of the renewable energy stations.

9. A computer device, characterized in that: include: one or more processors; a processor for executing one or more programs; When the one or more programs are executed by the one or more processors, a method for calculating the short-circuit ratio of multiple stations in a new energy cluster as described in any one of claims 1 to 4 is implemented.

10. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed, a method for calculating the short-circuit ratio of multiple stations in a new energy cluster as described in any one of claims 1 to 4 is implemented.

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