A subsynchronous oscillation monitoring device distribution method, device and medium

Abstract

The application discloses a subsynchronous oscillation monitoring device distribution method and device and a medium, and belongs to the technical field of power systems and their automation. In the power system, the proportion of wind power access is rising, and the risk of subsynchronous oscillation of the power grid is increasing. In order to effectively inhibit the spread of oscillation, it is necessary to configure a subsynchronous oscillation monitoring device in the power grid. Based on the new energy grid connection point with relatively low grid connection short-circuit calculated offline, the sub-super current components are injected into the power grid side from the station side, the subsynchronous oscillation propagation characteristics in the power grid are obtained, and the key nodes in the power grid which are strongly related to the subsynchronous oscillation are identified, and the monitoring device is configured. The application comprehensively considers the local weak nodes of new energy grid connection and the subsynchronous oscillation propagation characteristics, gives an oscillation monitoring device distribution scheme, and takes into account the economy of the monitoring system while ensuring the ability of the power grid to cope with the risk of subsynchronous oscillation.

Description

Technical Field

[0001] This invention discloses a method, device, and medium for deploying subsynchronous oscillation monitoring devices, belonging to the field of power system and automation technology. Background Technology

[0002] In addition to impacting the traditional stability of voltage, frequency, and power angle of the power grid, the large-scale integration of new energy power plants may also pose a new risk of subsynchronous frequency oscillations.

[0003] In recent years, this new type of oscillation problem has also appeared in actual engineering projects both domestically and internationally. Subsynchronous oscillations have also occurred in AC grid-connected wind turbine systems, drawing high attention from power grid operators to this new type of subsynchronous oscillation phenomenon.

[0004] The greatest danger of subsynchronous oscillations is that severe electromechanical coupling can directly lead to serious damage to the rotor shaft system of large steam turbine generator sets, causing major accidents and jeopardizing the safe operation of the power system. To effectively suppress the spread of oscillations, it is necessary to identify key nodes in the power grid that are strongly correlated with subsynchronous oscillations and to rationally configure subsynchronous oscillation monitoring devices within the power grid. However, current technologies struggle to identify key nodes and rationally configure subsynchronous oscillation monitoring devices. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method, device and medium for deploying subsynchronous oscillation monitoring devices. By reasonably configuring subsynchronous oscillation monitoring devices in the power grid, key nodes in the power grid that are strongly correlated with subsynchronous oscillations can be identified.

[0006] To achieve the above objectives, the present invention is implemented using the following technical solution:

[0007] In a first aspect, the present invention provides a method for deploying subsynchronous oscillation monitoring devices, comprising the following steps:

[0008] S1: Obtain the current power grid operation mode, calculate the short-circuit ratio of the new energy grid connection point, and establish an electromagnetic simulation model corresponding to the current power grid operation mode;

[0009] S2: Record all grid-connected points whose short-circuit ratio obtained in S1 is less than the preset short-circuit ratio value, sort them in descending order of short-circuit ratio and name them A1, A2, ..., A1. n Identification of the critical path for the propagation of subsynchronous oscillations starting from node A1;

[0010] S3: Based on the electromagnetic simulation model of S1, A i Nodes, i = 1, 2, ..., n, act as oscillation sources in A. i A current source module is added at the node bus to inject three-phase symmetrical currents at subsynchronous and supersynchronous frequencies into the power grid for electromagnetic simulation.

[0011] S4: By A i Starting at a node, monitor the subsynchronous oscillation power amplitude of all lines of the same voltage level connected to the node, and take the line with the largest amplitude as the critical branch for external propagation of the node. Then switch to the node on the opposite side of the critical branch and perform the same operation to search for the next critical branch. Continue in this way until the power amplitude in the searched critical branch is less than or equal to 0.1MW, and then stop the electromagnetic simulation.

[0012] S5: Record the critical branches in S4 and the nodes they pass through. For each node, calculate the ratio of the amplitude of its next-level critical branch to that of its previous-level critical branch, using this ratio as the propagation sensitivity coefficient for that node. End the current A. i Identification of critical propagation paths of nodes;

[0013] S6: Determine whether the critical path identification for oscillation propagation at all grid-connected points in S3 has been completed. If not, return to S3 and continue to the next A. i Identify the critical path for the subsynchronous oscillation propagation of the node; if all steps are completed, execute S7.

[0014] S7: Sum the propagation sensitivity coefficients of all nodes that appear in S5 under different oscillation sources to obtain their global propagation coefficients. Set a threshold ε and use the nodes with global propagation coefficients greater than ε as the configuration points of the monitoring device.

[0015] Furthermore, the preset value for the short-circuit ratio is 3.

[0016] Furthermore, in S1, the offline electromechanical data is exported from the power grid data platform;

[0017] The aforementioned new energy grid connection point refers to the busbar of the new energy power station; the short-circuit ratio of the new energy grid connection point is the ratio of the three-phase short-circuit current value at that point to the grid-connected new energy capacity, which can be calculated offline using professional software.

[0018] Furthermore, in S3, the three-phase symmetrical currents with secondary and supersynchronous frequencies, where the secondary and supersynchronous frequencies refer to frequency components less than and greater than 50Hz of the power frequency, respectively, and satisfy the following relationship:

[0019] f sub +f sup =2f0

[0020] The aforementioned injection of three-phase symmetrical current refers to injecting current in the following form:

[0021]

[0022] Where the subscripts a, b, and c represent phase sequence, I represents current amplitude, sub means subsynchronous, sup means supersynchronous, and Isub f sub Let α be the subsynchronous components of current and frequency, and let α represent the initial phase.

[0023] Furthermore, I sub The value is 0.01kA, I sup The value is 0.005 kA, α sub Take 0, α sup Take 50.

[0024] Furthermore, the electromagnetic simulation in S4 refers to using specialized software to perform time-domain simulation calculations on the electromagnetic model;

[0025] The subsynchronous oscillation power amplitude of the monitored line refers to the active power curve of the monitored line output in the simulation. Fourier analysis is performed on the active power curve of the monitored line output in the simulation to obtain the frequency f. sso The oscillation component is extracted and its amplitude is obtained, f sso The frequency of the injected current should satisfy the relationship f. sso =f0-f sub =f sup -f0.

[0026] Furthermore, the voltage level of the key branch in S5 is 500kV; ε is a preset threshold value used to ultimately screen nodes that meet the requirements, and can be set differently according to the monitoring range.

[0027] Secondly, the present invention provides a subsynchronous oscillation monitoring device deployment device, comprising the following steps:

[0028] Judgment module: used to obtain the current power grid operation mode, calculate the short-circuit ratio of the new energy grid connection point, and establish an electromagnetic simulation model corresponding to the current power grid operation mode;

[0029] Identification module: Used to record all grid connection points with a short-circuit ratio less than a preset short-circuit ratio value, sorted in descending order of short-circuit ratio and named A1, A2, ..., A n Identification of the critical path for the propagation of subsynchronous oscillations starting from node A1;

[0030] Electromagnetic simulation module: used to perform A simulations based on electromagnetic simulation models. i Nodes, i = 1, 2, ..., n, act as oscillation sources in A. i A current source module is added at the node bus to inject three-phase symmetrical currents at subsynchronous and supersynchronous frequencies into the power grid for electromagnetic simulation.

[0031] Search module: used by A iStarting at a node, monitor the subsynchronous oscillation power amplitude of all lines of the same voltage level connected to the node, and take the line with the largest amplitude as the critical branch for external propagation of the node. Then switch to the node on the opposite side of the critical branch and perform the same operation to search for the next critical branch. Continue in this way until the power amplitude in the searched critical branch is less than or equal to 0.1MW, and then stop the electromagnetic simulation.

[0032] Node module: Used to record critical branches and the nodes they pass through. For each node, it calculates the ratio of the amplitude of its next-level critical branch to that of its previous-level critical branch, which serves as the propagation sensitivity coefficient for that node. The current A module is then terminated. i Identification of critical propagation paths of nodes;

[0033] Judgment module: Used to determine whether the critical path identification of oscillation propagation at all grid-connected points in S3 has been completed. If not, continue to the next A. i Identification of critical paths for the propagation of subsynchronous oscillations at nodes;

[0034] Configuration module: used to sum the propagation sensitivity coefficients of all nodes under different oscillation sources to obtain their global propagation coefficient, set a threshold ε, and use nodes with a global propagation coefficient greater than ε as configuration points of the monitoring device.

[0035] Thirdly, the present invention provides a subsynchronous oscillation monitoring device deployment device, including a processor and a storage medium;

[0036] The storage medium is used to store instructions;

[0037] The processor is configured to operate according to the instructions to perform the steps of the method according to the first aspect.

[0038] Fourthly, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method described in the first aspect.

[0039] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0040] 1. This invention aims to effectively suppress the spread of oscillations by rationally configuring subsynchronous oscillation monitoring devices in the power grid, thereby identifying key nodes in the power grid that are strongly correlated with subsynchronous oscillations.

[0041] This invention uses offline calculations based on grid data to obtain new energy power plants with low grid-connected short-circuit ratios. Subsynchronous frequency band current components are injected into the grid side from each power plant to obtain the propagation characteristics of subsynchronous oscillation components in the grid, thereby identifying key nodes in the grid that are strongly correlated with subsynchronous oscillations and configuring monitoring devices.

[0042] This invention comprehensively considers the local weak nodes of new energy grid connection and the propagation characteristics of subsynchronous oscillations, and provides a deployment scheme for oscillation monitoring devices. It takes into account the economy of the monitoring system while ensuring the power grid's ability to cope with the risk of subsynchronous oscillations. Attached Figure Description

[0043] Figure 1 This is a flowchart of the method of the present invention. Detailed Implementation

[0044] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0045] Example 1:

[0046] To effectively suppress the spread of oscillations, a subsynchronous oscillation monitoring device is configured in the power grid. This embodiment uses offline calculations based on power grid data to identify new energy power plants with low grid-connected short-circuit ratios. Subsynchronous frequency band current components are injected from each power plant side into the power grid side to obtain the propagation characteristics of the subsynchronous oscillation component in the power grid. This allows for the identification of key nodes in the power grid strongly correlated with subsynchronous oscillations, and the configuration of monitoring devices accordingly.

[0047] This invention comprehensively considers the local weak nodes of new energy grid connection and the propagation characteristics of subsynchronous oscillations, and provides a deployment scheme for oscillation monitoring devices. It takes into account the economy of the monitoring system while ensuring the power grid's ability to cope with the risk of subsynchronous oscillations.

[0048] Specifically, this embodiment employs a method, device, and medium for deploying subsynchronous oscillation monitoring devices, including the following steps:

[0049] Step 1: Obtain the current power grid operation mode, calculate the short-circuit ratio of the new energy grid connection point, and establish an electromagnetic simulation model corresponding to the current power grid operation mode.

[0050] Step 2: Record all grid connection points with a short-circuit ratio less than 3 obtained in Step 1, sort them in descending order of short-circuit ratio, and name them A1, A2, ..., A i Identification of the critical path for the propagation of subsynchronous oscillations starting from node A1;

[0051] Step 3: Based on the electromagnetic simulation model from Step 1, A i The node acts as an oscillation source in A. i A current source module is added at the busbar of node (i = 1, 2, ..., n) to inject three-phase symmetrical currents at subsynchronous and supersynchronous frequencies into the power grid for electromagnetic simulation.

[0052] Step 4: From A iStarting at a node, monitor the subsynchronous oscillation power amplitude of all lines of the same voltage level connected to the node, and take the line with the largest amplitude as the critical branch for external propagation of the node. Then switch to the node on the opposite side of the critical branch and perform the same operation to search for the next critical branch. Continue in this way until the power amplitude in the searched critical branch is less than or equal to 0.1MW, and then stop the electromagnetic simulation.

[0053] Step 5: Record the critical branches and nodes they pass through in Step 4. For each node, calculate the ratio of the amplitude of its next-level critical branch to that of its previous-level critical branch. Use this ratio as the propagation sensitivity coefficient for that node. End the current A step. i Identification of critical propagation paths of nodes;

[0054] Step 6: Determine whether the critical path identification for oscillation propagation at all grid-connected points in Step 3 has been completed. If not, return to Step 3 and continue to the next A. i Identify the critical path for the propagation of subsynchronous oscillations at the nodes; if all are completed, proceed to step 7.

[0055] Step 7: Sum the propagation sensitivity coefficients of all nodes that appeared in Step 5 under different oscillation sources to obtain their global propagation coefficient. Set a threshold ε and use the nodes with a global propagation coefficient greater than ε as the configuration points of the monitoring device.

[0056] Preferably, the offline electromechanical data in step 1 can be exported from the power grid data platform; the new energy grid connection point refers to the collecting bus of the new energy power station; the grid connection point short-circuit ratio is the ratio of the three-phase short-circuit current value at that point to the grid-connected new energy capacity, which can be calculated offline using professional software.

[0057] Specifically, BPA and PSASP are preferred professional software options.

[0058] Preferably, in step 3, the three-phase symmetrical currents at the primary and supersynchronous frequencies, where the primary and supersynchronous frequencies refer to frequency components less than and greater than 50Hz of the power frequency, respectively, and satisfy the following relationship:

[0059] f sub +f sup =2f0

[0060] The aforementioned injection of three-phase symmetrical current refers to injecting current in the following form:

[0061]

[0062] Where the subscripts a, b, and c represent the phase sequence, I represents the current amplitude, Isub can be 0.01kA, Isup can be 0.005kA, α represents the initial phase, and α... sub It can be 0, α sup 50 is acceptable.

[0063] Preferably, the electromagnetic simulation in step 4 refers to performing time-domain simulation calculations on the electromagnetic model from step 4 using specialized software (PSASP is an option); the monitored line subsynchronous oscillation power amplitude refers to obtaining the frequency f by performing Fourier analysis on the active power curve of the monitored line output in the simulation. sso The oscillation component is extracted and its amplitude is obtained, f sso The frequency of the injected current should satisfy the relationship f. sso =f0-f sub =f sup -f0.

[0064] Preferably, the voltage level of the key branch in step 8 is 500kV; ε is a preset threshold value used to finally screen nodes that meet the requirements, and can be set differently according to the monitoring range.

[0065] Example 2:

[0066] This embodiment provides a subsynchronous oscillation monitoring device deployment device, including the following steps:

[0067] Judgment module: used to obtain the current power grid operation mode, calculate the short-circuit ratio of the new energy grid connection point, and establish an electromagnetic simulation model corresponding to the current power grid operation mode;

[0068] Identification module: Used to record all grid connection points with a short-circuit ratio less than a preset short-circuit ratio value, sorted in descending order of short-circuit ratio and named A1, A2, ..., A n Identification of the critical path for the propagation of subsynchronous oscillations starting from node A1;

[0069] Electromagnetic simulation module: used to perform A simulations based on electromagnetic simulation models. i Nodes, i = 1, 2, ..., n, act as oscillation sources in A. i A current source module is added at the node bus to inject three-phase symmetrical currents at subsynchronous and supersynchronous frequencies into the power grid for electromagnetic simulation.

[0070] Search module: used by A i Starting at a node, monitor the subsynchronous oscillation power amplitude of all lines of the same voltage level connected to the node, and take the line with the largest amplitude as the critical branch for external propagation of the node. Then switch to the node on the opposite side of the critical branch and perform the same operation to search for the next critical branch. Continue in this way until the power amplitude in the searched critical branch is less than or equal to 0.1MW, and then stop the electromagnetic simulation.

[0071] Node module: Used to record critical branches and the nodes they pass through. For each node, it calculates the ratio of the amplitude of its next-level critical branch to that of its previous-level critical branch, which serves as the propagation sensitivity coefficient for that node. The current A module is then terminated. i Identification of critical propagation paths of nodes;

[0072] Judgment module: Used to determine whether the critical path identification of oscillation propagation at all grid-connected points in S3 has been completed. If not, continue to the next A. i Identification of critical paths for the propagation of subsynchronous oscillations at nodes;

[0073] Configuration module: used to sum the propagation sensitivity coefficients of all nodes under different oscillation sources to obtain their global propagation coefficient, set a threshold ε, and use nodes with a global propagation coefficient greater than ε as configuration points of the monitoring device.

[0074] The apparatus in this embodiment can be used to implement the method described in Embodiment 1.

[0075] Example 3:

[0076] This embodiment provides a subsynchronous oscillation monitoring device deployment device, including a processor and a storage medium;

[0077] The storage medium is used to store instructions;

[0078] The processor is configured to operate according to the instructions to perform the steps of the method according to Embodiment 1.

[0079] Example 4:

[0080] This embodiment provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method described in Embodiment 1.

[0081] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application 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.

[0082] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. 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... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0083] 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.

[0084] 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.

[0085] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for deploying subsynchronous oscillation monitoring devices, characterized in that, Includes the following steps: S1: Obtain the current power grid operation mode, calculate the short-circuit ratio of the new energy grid connection point, and establish an electromagnetic simulation model corresponding to the current power grid operation mode; S2: Record all grid-connected points whose short-circuit ratio obtained in S1 is less than the preset short-circuit ratio value, sort them in descending order of short-circuit ratio and name them A1, A2, ..., A1. n Identification of the critical path for the propagation of subsynchronous oscillations starting from node A1; S3: Based on the electromagnetic simulation model of S1, A i Nodes, i=1, 2, ..., n, act as oscillation sources in A. i A current source module is added at the node bus to inject three-phase symmetrical currents at subsynchronous and supersynchronous frequencies into the power grid for electromagnetic simulation. S4: By A i The node starts by monitoring the subsynchronous oscillation power amplitude of all lines of the same voltage level connected to the node. The line with the largest amplitude is taken as the critical branch for external propagation of the node. Then, the same operation is performed on the node opposite the critical branch to search for the next critical branch. The electromagnetic simulation stops when the power amplitude of the searched critical branch is less than or equal to the power amplitude threshold. S5: Record the critical branches in S4 and the nodes they pass through. For each node, calculate the ratio of the amplitude of its next-level critical branch to that of its previous-level critical branch, using this ratio as the propagation sensitivity coefficient for that node. End the current A. i Identification of critical propagation paths of nodes; S6: Determine whether the critical path identification for oscillation propagation at all grid-connected points in S3 has been completed. If not, return to S3 and continue to the next A. i Identify the critical path for the subsynchronous oscillation propagation of the node; if all steps are completed, execute S7. S7: Sum the propagation sensitivity coefficients of all nodes appearing in S5 under different oscillation sources to obtain their global propagation coefficient, and set a threshold. The global propagation coefficient is greater than The nodes serve as the configuration points for the monitoring devices; The injected three-phase symmetrical current at the secondary and supersynchronous frequencies in S3, where the secondary and supersynchronous frequencies refer to frequency components less than and greater than 50Hz of the power frequency, respectively, and satisfy the following relationship: ； The aforementioned injection of three-phase symmetrical current refers to injecting current in the following form: ； Where the subscripts a, b, and c represent phase sequence, I represents current amplitude, sub means subsynchronous, sup means supersynchronous, and I sub f sub Let α represent the subsynchronous components of current and frequency, and let α represent the initial phase.

2. The method for deploying subsynchronous oscillation monitoring devices according to claim 1, characterized in that, The preset value for the short-circuit ratio is 3; The power amplitude threshold is 0.1MW.

3. The method for deploying subsynchronous oscillation monitoring devices according to claim 1, characterized in that, In step S1, the offline electromechanical data is exported from the power grid data platform; The aforementioned new energy grid connection point refers to the busbar of the new energy power station; the short-circuit ratio of the new energy grid connection point is the ratio of the three-phase short-circuit current value at that point to the grid-connected new energy capacity, which is calculated offline using professional software.

4. The method for deploying subsynchronous oscillation monitoring devices according to claim 1, characterized in that, I sub The value is 0.01kA, I sup The value is 0.005 kA, α sub Take 0, α sup Take 50.

5. The method for deploying subsynchronous oscillation monitoring devices according to claim 1, characterized in that, The electromagnetic simulation in S4 refers to the time-domain simulation calculation of the electromagnetic model using specialized software. The subsynchronous oscillation power amplitude of the monitored line refers to the active power curve of the monitored line output in the simulation. Fourier analysis is performed on the active power curve of the monitored line output in the simulation to obtain the frequency f. sso The oscillation component is extracted and its amplitude is obtained, f sso The frequency of the injected current should satisfy the following relationship: .

6. The method for deploying subsynchronous oscillation monitoring devices according to claim 1, characterized in that, The voltage level of the key branch in S5 is 500kV; The preset threshold is used to ultimately filter nodes that meet the requirements, and different settings can be made according to the monitoring range.

7. A device for deploying subsynchronous oscillation monitoring devices for performing the method as described in claim 1, characterized in that, Includes the following steps: Judgment module: used to obtain the current power grid operation mode, calculate the short-circuit ratio of the new energy grid connection point, and establish an electromagnetic simulation model corresponding to the current power grid operation mode; Identification module: Used to record all grid connection points with a short-circuit ratio less than a preset short-circuit ratio value, sorted in descending order of short-circuit ratio and named A1, A2, ..., A n Identification of the critical path for the propagation of subsynchronous oscillations starting from node A1; Electromagnetic simulation module: used to perform A simulations based on electromagnetic simulation models. i Nodes, i=1, 2, ..., n, act as oscillation sources in A. i A current source module is added at the node bus to inject three-phase symmetrical currents at subsynchronous and supersynchronous frequencies into the power grid for electromagnetic simulation. Search module: used by A i At the start of a node, monitor the subsynchronous oscillation power amplitude of all lines of the same voltage level connected to the node, and take the line with the largest amplitude as the critical branch for external propagation of the node. Then switch to the node on the opposite side of the critical branch and perform the same operation to search for the next critical branch. Stop the electromagnetic simulation when the power amplitude in the searched critical branch is less than or equal to 0.1MW. Node module: Used to record critical branches and the nodes they pass through. For each node, it calculates the ratio of the amplitude of its next-level critical branch to that of its previous-level critical branch, which serves as the propagation sensitivity coefficient for that node. The current A module is then terminated. i Identification of critical propagation paths of nodes; Judgment module: Used to determine whether the critical path identification of oscillation propagation at all grid-connected points in S3 has been completed. If not, continue to the next A. i Identification of critical paths for the propagation of subsynchronous oscillations at nodes; Configuration module: Used to sum the propagation sensitivity coefficients of all nodes under different oscillation sources to obtain their global propagation coefficient, and to set a threshold. The global propagation coefficient is greater than The nodes serve as the configuration points for the monitoring devices.

8. A device for deploying subsynchronous oscillation monitoring equipment, characterized in that, Including processor and storage media; The storage medium is used to store instructions; The processor is configured to operate according to the instructions to perform the steps of the method according to any one of claims 1-6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps of the method as described in any one of claims 1-6.

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