New energy unit stability characteristic analysis and discrimination method

Abstract

The invention discloses a new energy unit stability characteristic analysis and discrimination method, and belongs to the technical field of power system control, and the method comprises the steps: obtaining key parameters of a high-proportion new energy system, a new energy unit and an equivalent new energy unit; calculating an equivalent damping coefficient of the high-proportion new energy system according to the key parameters of the high-proportion new energy system, the new energy unit and the equivalent new energy unit in combination with pre-read real-time data of the high-proportion new energy system, the new energy unit and the power grid; according to the equivalent damping coefficient of the high-proportion new energy system, whether synchronous instability of the high-proportion new energy system occurs or not is judged; according to the method, the synchronous operation capability of the new energy unit is effectively evaluated, so that the synchronous stability of the high-proportion new energy system is ensured.

Description

Technical Field

[0001] The invention relates to a method for analyzing and judging the stability characteristics of a new energy unit, and belongs to the technical field of power system control. Background Art

[0002] In recent years, more and more new energy units are being connected to the power system, and the power system's ability to resist serious grid failures has been weakening. Recent studies have shown that it is difficult for new energy to keep pace with the power system under large grid disturbances, which restricts the power system's ability to absorb new energy units.

[0003] For traditional power systems dominated by synchronous machines, the synchronous operation problem between the unit and the power grid is mainly considered as a power angle stability problem. By calculating the acceleration and deceleration areas related to energy, the synchronous operation capability of the high-proportion renewable energy power system is estimated. In the above studies, synchronous generators are often assumed to be AC ​​power sources with constant positive damping. However, for new power systems dominated by renewable energy, the equivalent damping effect has a time-varying sign in the transient process after the disturbance, which makes the renewable energy system likely to exhibit a negative damping dissipation effect, thereby worsening the synchronous stability of the system and causing synchronous instability of the renewable energy unit.

[0004] In response to the above problems, existing research often achieves qualitative characterization of the synchronous operation capability of the unit by monitoring indicators such as the power angle of the synchronous generator and the phase-locking angle of the new energy unit. However, the above indicators often cannot reveal the mechanism, and their indication of the synchronous operation capability lacks a theoretical basis. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a method for analyzing and judging the stability characteristics of a new energy unit, so as to effectively evaluate the synchronous operation capability of the new energy unit and ensure the synchronous stability of a high-proportion new energy system.

[0006] To achieve the above object, the present invention is implemented by adopting the following technical solutions:

[0007] In a first aspect, the present invention provides a method for analyzing and determining the stability characteristics of a new energy unit, comprising:

[0008] Obtain key parameters of high-proportion new energy systems, new energy units, and equivalent new energy units;

[0009] According to the key parameters of the high-proportion new energy system, the new energy unit and the equivalent new energy unit, combined with the pre-read real-time data of the high-proportion new energy system, the new energy unit and the power grid, the equivalent damping coefficient of the high-proportion new energy system is calculated;

[0010] According to the equivalent damping coefficient of the high-proportion new energy system, it is judged whether the high-proportion new energy system will suffer from synchronous instability.

[0011] Furthermore, the key parameters of the high-proportion new energy system and new energy units are obtained, including:

[0012] Obtain the parameters of the high-proportion new energy system, including: damping coefficient D1, inertia coefficient J1, where D1> 0, J1> 0;

[0013] Get the parameters of the new energy unit, including: the proportional coefficient k of the phase-locked loop p , the integral coefficient k of the phase-locked loop i , where k p > 0, k i > 0;

[0014] Get the parameters of equivalent new energy units, including: equivalent potential U g ,frequency w g , equivalent impedance Z 3= R 3+ j w g L 3. Grid-connected impedance of new energy units Z 1= R 1+ j w g L 1. Grid-connected impedance of new energy units Z 2= R 2+ j w g L 2;

[0015] Among them, R1>0, R2>0, R3>0, L1>0, L2>0, L3>0, U g > 0, w g = 2*pi*50, R1, R2, R3 are the grid-connected resistances of the new energy units, L1, L2, L3 are the grid-connected inductors of the new energy units, pi is a mathematical constant representing the ratio of pi, and j is an imaginary unit.

[0016] Furthermore, the pre-read real-time data of the high-proportion new energy system, new energy units and power grid include:

[0017] Read the real-time data of the high-proportion new energy system, including: the power angle δ1, speed of the high-proportion new energy system w 1;

[0018] Read the real-time data of the new energy unit, including: the phase-lock angle δ2 of the new energy unit, the virtual speed w 2. Active current i injected into the grid by new energy d2 ,in:

[0019] (1);

[0020] Among them, I max is the maximum permissible current of the power electronic power supply;

[0021] Read the real-time data of the power grid, including: the active voltage component u of the collection bus of the new energy unit and the power grid x3 and reactive voltage component u y3 ;

[0022] The voltage amplitude U3 of the collection bus is set to meet the voltage constraint of the AC bus. The formula is as follows:

[0023] (2);

[0024] Among them, U 3max It is the maximum allowable voltage of the power electronic power supply.

[0025] Furthermore, the calculation of the equivalent damping coefficient of the high-proportion new energy system includes:

[0026] Calculate the equivalent inertia J2 of the new energy unit, the formula is as follows:

[0027] (3);

[0028] Calculate the equivalent damping D2 of the new energy unit, the formula is as follows:

[0029] (4);

[0030] Calculation of equivalent damping D of high-proportion new energy systems eq , the formula is as follows:

[0031] (5).

[0032] Further, judging whether the high-proportion new energy system will suffer from synchronous instability according to the equivalent damping coefficient of the high-proportion new energy system includes:

[0033] If D eq > 0, the high-proportion new energy system will not experience synchronous instability;

[0034] If D eq < 0, the high-proportion new energy system will experience synchronous instability;

[0035] If Deq If the sign of changes alternately between positive and negative over time, the energy dissipation value E of the damping effect is monitored and calculated. If E is greater than 0, the high-proportion new energy units resume synchronous and stable operation. If E is less than 0, the high-proportion new energy system tends to synchronous instability.

[0036] Furthermore, the energy dissipation value E of the damping effect is calculated as follows:

[0037] (6).

[0038] In a second aspect, the present invention provides a device for analyzing and determining the stability characteristics of a new energy unit, comprising:

[0039] An acquisition module is used to obtain key parameters of a high-proportion new energy system, a new energy unit, and an equivalent new energy unit;

[0040] A calculation module, for calculating the equivalent damping coefficient of the high-proportion new energy system according to key parameters of the high-proportion new energy system, the new energy unit and the equivalent new energy unit, combined with pre-read real-time data of the high-proportion new energy system, the new energy unit and the power grid;

[0041] The judgment module is used to judge whether the high-proportion new energy system will suffer from synchronous instability according to the equivalent damping coefficient of the high-proportion new energy system.

[0042] In a third aspect, 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 any of the aforementioned methods.

[0043] In a fourth aspect, the present invention provides a computer device, comprising:

[0044] Memory, for storing computer programs / instructions;

[0045] A processor is used to execute the computer program / instructions to implement the steps of any of the aforementioned methods.

[0046] In a fifth aspect, the present invention provides a computer program product, comprising a computer program / instruction, which implements the steps of any one of the aforementioned methods when executed by a processor.

[0047] Compared with the prior art, the present invention has the following beneficial effects:

[0048] The present invention provides a method for analyzing and judging the stability characteristics of a new energy unit, by calculating the equivalent damping coefficient of a high-proportion new energy system; based on the equivalent damping coefficient of the high-proportion new energy system, it is judged whether the high-proportion new energy system will experience synchronous instability, which can effectively evaluate the synchronous operation capability of the new energy unit and ensure that the synchronous stability of the entire high-proportion new energy system is guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a flow chart of a method for analyzing and judging the stability characteristics of a new energy unit provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0050] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0051] Embodiment 1: This embodiment introduces a method for analyzing and judging the stability characteristics of a new energy unit, including:

[0052] Obtain key parameters of high-proportion new energy systems, new energy units, and equivalent new energy units;

[0053] According to the key parameters of the high-proportion new energy system, the new energy unit and the equivalent new energy unit, combined with the pre-read real-time data of the high-proportion new energy system, the new energy unit and the power grid, the equivalent damping coefficient of the high-proportion new energy system is calculated;

[0054] According to the equivalent damping coefficient of the high-proportion new energy system, it is judged whether the high-proportion new energy system will suffer from synchronous instability.

[0055] like Figure 1 As shown, the application process of the new energy unit stability characteristic analysis and judgment method provided in this embodiment specifically involves the following steps:

[0056] (1) Construct a new energy unit model and obtain parameters. Based on the measured data of the power grid and the parameter identification method, identify the key parameters of the high-proportion new energy units. The key parameters involved include the key parameters of the new energy unit control system and the key parameters of the equivalent new energy units.

[0057] (2) Reading and recording real-time data, including reading and recording key data of high-proportion new energy units in real time based on the online monitoring device of the power grid. The key data involved include key data of the control system of the new energy units and key data of equivalent new energy units;

[0058] (3) Calculate the equivalent damping coefficient of high-proportion new energy units;

[0059] (4) Identify synchronous instability of high-proportion new energy units.

[0060] The specific steps include:

[0061] Step 1: Build a new energy unit model and obtain parameters. Based on the measured data of the power grid and the parameter identification method, identify the key parameters of the high-proportion new energy units. The key parameters involved include the key parameters of the new energy unit control system and the key parameters of the equivalent new energy units.

[0062] Since this patent mainly focuses on the synchronization stability of high-proportion new energy units, the parameters it focuses on mainly involve the synchronization units of various power sources in the high-proportion new energy system, that is, the virtual oscillator interface power supply with a second-order inertia link. The specific parameters involved include:

[0063] Step 1.1: Obtain the parameters of the high-proportion new energy system

[0064] The parameters of the high-proportion new energy system include: damping coefficient D1, inertia coefficient J1.

[0065] The above two parameters are mainly obtained by actual measurement and parameter conversion. The value ranges of the two parameters are D1> 0 and J1> 0 respectively. Considering the actual physical process, parameter J1 is generally much larger than parameter D1.

[0066] Step 1.2: Obtain the parameters of the new energy unit

[0067] The proportionality factor k of the phase-locked loop p , the integral coefficient k of the phase-locked loop i .

[0068] The above two parameters are mainly obtained through actual measurement, and the range of the two parameters is k p > 0, k i > 0, considering the actual physical process, the parameter k i Generally much larger than parameter k p .

[0069] Step 1.3: Obtain the parameters of the equivalent new energy unit

[0070] Equivalent potential U g ,frequency w g , equivalent impedance Z 3= R 3+ j w g L 3. Grid-connected impedance of new energy units Z 1= R 1+ j w g L 1. Grid-connected impedance of new energy units Z2= R 2+ j w g L 2.

[0071] The above parameters are mainly obtained through actual measurement and parameter conversion. The value range of each parameter is R1> 0, R2> 0, R3> 0, L1> 0, L2> 0, L3> 0, U g > 0, w g = 2*pi*50, R1, R2, R3 are the grid-connected resistances of the new energy units, L1, L2, L3 are the grid-connected inductors of the new energy units, pi is a mathematical constant representing the ratio of pi, j is an imaginary unit. Considering the actual physical process, parameters R1, R2, R3 are generally much smaller than parameters L1, L2, L3.

[0072] Step 2: Read and record the real-time data of the new energy units, including reading and recording the key data of the high-proportion new energy units in real time based on the online monitoring device of the power grid. The key data involved include the key data of the new energy unit control system and the key data of the equivalent new energy units.

[0073] Since this patent mainly focuses on the synchronous stability of high-proportion new energy units, the parameters it focuses on mainly involve the synchronous units of various power sources in the high-proportion new energy system, that is, the virtual oscillator interface power supply with a second-order inertia link. The specific data involved include:

[0074] Step 2.1: Read the real-time data of the high-proportion new energy system;

[0075] The data read include: power angle δ1, speed of high-proportion new energy system w 1；

[0076] The above two parameters are mainly obtained through actual measurement. The measurement of parameters can be selected on the main body of the new energy unit, or through the active and reactive power injected into the grid by the new energy unit to achieve online estimation. Considering the actual physical process, the real-time data δ1 is an angle system data, and the value range of the data generally does not exceed 180°. w 1 is the speed data, and the value range of the data is generally not more than 2 times w g .

[0077] Step 2.2: Read the real-time data of the new energy unit

[0078] The data read include: phase lock angle δ2 of new energy units, virtual speed w 2. Active current i injected into the grid by new energy d2；

[0079] The above two parameters are mainly obtained by actual measurement. The measurement of parameters can be selected in the converter control system on the grid side of the new energy unit, or it can be estimated online through the active and reactive power injected into the grid by the new energy unit. Considering the actual physical process, the real-time data δ2 is an angle data, and the value range of the data generally does not exceed 180°. w 2 is the speed data, and the value range of the data is generally not more than 5 times w g , current data i d2 It is related to the actual power injection capability, and its value range depends on physical constraints such as the current-carrying and voltage-withstanding capability of the power electronic power supply, that is,

[0080] (1)

[0081] Among them, I max It is the maximum allowable current of the power electronic power supply and is directly related to the current carrying capacity.

[0082] Step 2.3: Read real-time data from the power grid

[0083] The data read include: the active voltage component u of the collection bus of the new energy unit and the power grid x3 and reactive voltage component u y3 .

[0084] The above two parameters are mainly obtained through actual measurement. Considering the actual physical process, the voltage amplitude U3 of the collection bus must meet the voltage constraint of the AC bus, that is,

[0085] (2)

[0086] Among them, U 3max It is the maximum allowable voltage of the power electronic power supply, which is directly related to the voltage withstand capability of the AC line.

[0087] Step 3: Calculate the equivalent damping coefficient of high-proportion new energy units.

[0088] Step 3.1: Calculation of equivalent inertia of new energy units

[0089] Based on the above identified grid parameters (L1, L2, L3, k p ), online monitoring data (i d2 ), which can realize the online calculation of the equivalent inertia of the new energy unit. The calculation of the equivalent inertia of the new energy unit can be based on the following expression:

[0090] (3)

[0091] Step 3.2: Calculation of equivalent damping of new energy units

[0092] Based on the above identified grid parameters (L1, L2, L3, k p , k i ), online monitoring data (i d2 、u x3 、u y3 , δ2), can realize the online calculation of the equivalent damping of the new energy unit. The calculation of the equivalent damping of the new energy unit can be based on the following expression:

[0093] (4)

[0094] Step 3.3: Equivalent damping calculation of high-proportion new energy system

[0095] The equivalent damping of a high-proportion renewable energy system depends on the damping coefficient D1 of the synchronous generator and the equivalent damping D2 of the renewable energy unit. The weight relationship between the above two parameters depends on the inertia coefficient J1 of the synchronous generator and the equivalent inertia J2 of the renewable energy unit. The calculation of the equivalent damping of a high-proportion renewable energy system can be based on the following expression:

[0096] (5)

[0097] Step 4: Identify synchronous instability of high-proportion new energy units.

[0098] Based on the above calculation, the equivalent damping D of the high-proportion new energy system eq , to judge the synchronous operation capability of new energy units in the power system.

[0099] If there is always D eq > 0, the high-proportion renewable energy system will not experience synchronous instability, and the transient energy of each renewable energy unit in the high-proportion renewable energy system is within the equivalent damping D eq Finally, the high-proportion new energy units resume synchronous and stable operation.

[0100] If there is always D eq < 0, the high-proportion renewable energy system will experience synchronous instability, and the transient energy of each renewable energy unit in the high-proportion renewable energy system will be in the equivalent damping D eq , failed to dissipate quickly, and eventually a high proportion of new energy units suffered synchronous instability.

[0101] If D eq If the sign of changes alternately between positive and negative over time, it is necessary to further monitor and calculate the energy dissipation value E of the damping effect, and its mathematical expression is:

[0102] (6)

[0103] If E> 0, the transient energy of each renewable energy unit in the high-proportion renewable energy system is in the equivalent damping D eq Finally, the high-proportion new energy units resume synchronous and stable operation.

[0104] If E< 0, the high-proportion renewable energy system tends to be synchronously unstable, and the transient energy of each renewable energy unit in the high-proportion renewable energy system is in the equivalent damping D eq , failed to dissipate quickly, and eventually a high proportion of new energy units suffered synchronous instability.

[0105] Embodiment 2: This embodiment provides a device for analyzing and determining the stability characteristics of a new energy unit, including:

[0106] An acquisition module is used to obtain key parameters of a high-proportion new energy system, a new energy unit, and an equivalent new energy unit;

[0107] A calculation module, for calculating the equivalent damping coefficient of the high-proportion new energy system according to key parameters of the high-proportion new energy system, the new energy unit and the equivalent new energy unit, combined with pre-read real-time data of the high-proportion new energy system, the new energy unit and the power grid;

[0108] The judgment module is used to judge whether the high-proportion new energy system will suffer from synchronous instability according to the equivalent damping coefficient of the high-proportion new energy system.

[0109] The specific functional implementation of each of the above modules can be found in the relevant contents of the method in Example 1 and will not be elaborated here.

[0110] Embodiment 3, this embodiment provides a computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, the steps of any one of the methods described in Embodiment 1 are implemented.

[0111] Embodiment 4: This embodiment provides a computer device, including:

[0112] Memory, for storing computer programs / instructions;

[0113] A processor, configured to execute the computer program / instructions to implement the steps of any one of the methods described in Example 1.

[0114] Embodiment 5: This embodiment provides a computer program product, including a computer program / instruction, which implements the steps of any method described in Embodiment 1 when executed by a processor.

[0115] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

[0116] It should be understood by those skilled in the art that the embodiments of the present disclosure may be provided as methods, systems or computer program products. Therefore, the present disclosure may take the form of a complete hardware embodiment, a complete software embodiment or an embodiment combining software and hardware aspects. Moreover, the present disclosure 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.

[0117] The present disclosure is described with reference to flowcharts and / or block diagrams of methods, devices (systems) and computer program products according to embodiments of the present disclosure. It should be understood that each process and / or block in the flowchart and / or block diagram and 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.

[0118] 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 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0119] 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.

[0120] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure rather than to limit its protection scope. Although the present disclosure has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that after reading the present disclosure, those skilled in the art can still make various changes, modifications or equivalent substitutions to the specific implementation methods of the invention, but these changes, modifications or equivalent substitutions are all within the protection scope of the disclosed claims to be approved.

Claims

1. A method for analyzing and judging the stability characteristics of a new energy unit, characterized in that: include: Obtain key parameters of high-proportion new energy systems, new energy units, and equivalent new energy units; According to the key parameters of the high-proportion new energy system, the new energy unit and the equivalent new energy unit, combined with the pre-read real-time data of the high-proportion new energy system, the new energy unit and the power grid, the equivalent damping coefficient of the high-proportion new energy system is calculated; According to the equivalent damping coefficient of the high-proportion new energy system, it is judged whether the high-proportion new energy system will suffer from synchronous instability.

2. The method for analyzing and determining the stability characteristics of a new energy unit according to claim 1 is characterized in that: The key parameters of the high-proportion new energy system and new energy units are obtained, including: Obtain the parameters of the high-proportion new energy system, including: damping coefficient D1, inertia coefficient J1, where D1> 0, J1> 0; Get the parameters of the new energy unit, including: the proportional coefficient k of the phase-locked loop p , the integral coefficient k of the phase-locked loop i , where k p >0,k i > 0; Get the parameters of equivalent new energy units, including: equivalent potential U g ,frequency w g , equivalent impedance Z 3= R 3+ j w g L 3. Grid-connected impedance of new energy units Z 1= R 1+ j w g L 1. Grid-connected impedance of new energy units Z 2= R 2+ j w g L 2; Among them, R1>0, R2>0, R3>0, L1>0, L2>0, L3>0, U g > 0, w g = 2*pi*50, R1, R2, R3 are the grid-connected resistances of the new energy units, L1, L2, L3 are the grid-connected inductors of the new energy units, pi is a mathematical constant representing the ratio of pi, and j is an imaginary unit.

3. The method for analyzing and determining the stability characteristics of a new energy unit according to claim 2 is characterized in that: The pre-read real-time data of the high-proportion new energy system, new energy units and power grid include: Read the real-time data of the high-proportion new energy system, including: the power angle δ1, speed of the high-proportion new energy system w 1; Read the real-time data of the new energy unit, including: the phase-lock angle δ2 of the new energy unit, the virtual speed w 2. Active current i injected into the grid by new energy d2 ,in: （1）； Among them, I max is the maximum permissible current of the power electronic power supply; Read the real-time data of the power grid, including: the active voltage component u of the collection bus of the new energy unit and the power grid x3 and reactive voltage component u y3 ; The voltage amplitude U3 of the collection bus is set to meet the voltage constraint of the AC bus. The formula is as follows: （2）； Among them, U 3max It is the maximum allowable voltage of the power electronic power supply.

4. The method for analyzing and determining the stability characteristics of a new energy unit according to claim 3 is characterized in that: The calculation of the equivalent damping coefficient of the high-proportion new energy system includes: Calculate the equivalent inertia J2 of the new energy unit, the formula is as follows: （3）； Calculate the equivalent damping D2 of the new energy unit, the formula is as follows: （4）； Calculation of equivalent damping D of high-proportion new energy systems eq , the formula is as follows: （5）。 5. The method for analyzing and determining the stability characteristics of new energy units according to claim 4 is characterized in that: The step of judging whether the high-proportion new energy system will experience synchronous instability according to the equivalent damping coefficient of the high-proportion new energy system includes: If D eq > 0, the high-proportion new energy system will not experience synchronous instability; If D eq < 0, the high-proportion new energy system will experience synchronous instability; If D eq If the sign of changes alternately between positive and negative over time, the energy dissipation value E of the damping effect is monitored and calculated. If E is greater than 0, the high-proportion new energy units resume synchronous and stable operation. If E is less than 0, the high-proportion new energy system tends to synchronous instability.

6. The method for analyzing and determining the stability characteristics of a new energy unit according to claim 5 is characterized in that: The energy dissipation value E of the damping effect is calculated as follows: （6）。 7. A device for analyzing and determining the stability characteristics of a new energy unit, characterized in that: include: An acquisition module is used to obtain key parameters of a high-proportion new energy system, a new energy unit, and an equivalent new energy unit; A calculation module, for calculating the equivalent damping coefficient of the high-proportion new energy system according to key parameters of the high-proportion new energy system, the new energy unit and the equivalent new energy unit, combined with pre-read real-time data of the high-proportion new energy system, the new energy unit and the power grid; The judgment module is used to judge whether the high-proportion new energy system will suffer from synchronous instability according to the equivalent damping coefficient of the high-proportion new energy system.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method described in any one of claims 1 to 6 are implemented.

9. A computer device, characterized in that: include: Memory, for storing computer programs / instructions; A processor, configured to execute the computer program / instructions to implement the steps of the method according to any one of claims 1 to 6.

10. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instructions are executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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