A low-voltage power distribution area three-phase identification method, system, device and medium

Abstract

This invention belongs to the field of power system technology and discloses a three-phase identification method for low-voltage distribution transformer areas. The method includes: installing data acquisition units for emitting topological characteristic currents on each power supply branch of the low-voltage distribution transformer area, and installing a fusion terminal at the main incoming line of the low-voltage distribution transformer area; using phase B of each power supply branch as a reference angle, injecting topological characteristic currents from phase B of the corresponding power supply branch through the data acquisition units, and acquiring voltage data of phases A and C of the corresponding power supply branch through the fusion terminal; calculating the phase angles of phases A and C of the corresponding power supply branch based on the voltage data, comparing these phase angles with the reference angles, and determining the three-phase sequence of the corresponding power supply branch based on the comparison results. This invention can accurately identify the phase sequence and phase of each power supply branch in a low-voltage distribution transformer area, thereby ensuring accurate calculation of electricity consumption for each phase, providing an effective basis for single-phase load adjustment of each branch, reducing line losses, and effectively identifying electricity theft.

Description

Technical Field

[0001] This invention relates to the field of power system technology, and in particular to a method, system, equipment and medium for three-phase identification of low-voltage distribution substations. Background Technology

[0002] With the smooth progress of my country's power market reform and the increasing tension in energy supply, the country has set higher requirements for improving the quality and reducing costs of the power grid's economic operation. Low-voltage distribution area power loss (distribution area line loss) accounts for a high proportion of energy loss throughout the entire power transmission process. Insufficient monitoring and analysis technology, outdated management and governance methods, and persistent electricity theft limit the improvement of the overall energy efficiency of the power grid. The root cause of this problem is the complex wiring of power supply areas, making it difficult to ensure phase consistency across the three phases. To solve this problem, accurate phase identification of low-voltage power supply areas is necessary for phase-by-phase power accumulation and data analysis.

[0003] Therefore, how to provide a low-voltage distribution area current identification technology is an urgent problem to be solved. Summary of the Invention

[0004] This invention provides a three-phase identification method, system, device, and medium for low-voltage distribution transformer areas. It can accurately identify the phase sequence and phase of each power supply branch in a low-voltage power supply transformer area, thereby ensuring accurate calculation of the power consumption of each phase, providing an effective basis for adjusting the single-phase load of each branch, reducing line loss, and effectively identifying electricity theft.

[0005] To provide a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. This summary is not intended as a general commentary, nor is it intended to identify key / important components or to describe the scope of protection of these embodiments. Its sole purpose is to present some concepts in a simple form as a prelude to the detailed description that follows.

[0006] According to a first aspect of the present invention, a three-phase identification method for low-voltage distribution transformer areas is provided.

[0007] In one embodiment, the three-phase identification method for low-voltage distribution substations includes:

[0008] Data acquisition units for transmitting topological characteristic currents are installed on each power supply branch of the low-voltage distribution transformer area, and a fusion terminal is installed at the main incoming line of the low-voltage distribution transformer area.

[0009] Using phase B of each power supply branch as the reference angle, the data acquisition unit injects topological characteristic current from phase B into the corresponding power supply branch, and the fusion terminal collects the voltage data of phase A and phase C of the corresponding power supply branch.

[0010] Based on the voltage data, the phase angles of phases A and C of the corresponding power supply branch are calculated, and the phase angles are compared with the reference angles. Based on the comparison results, the three-phase sequence of the corresponding power supply branch is determined.

[0011] In one embodiment, comparing the phase angle with the reference angle and determining the three-phase sequence of the corresponding power supply branch based on the comparison result includes: comparing the phase angle with the reference angle; if the comparison result shows that the voltage of phase A exceeds phase B by 120° and the voltage of phase C lags phase B by 120°, the three-phase sequence of the corresponding power supply branch is determined to be a positive phase sequence; otherwise, the three-phase sequence of the corresponding power supply branch is determined to be a negative phase sequence.

[0012] In one embodiment, the three-phase identification method for low-voltage distribution substations further includes: if the determination result is that the three-phase sequence of the corresponding power supply branch is reversed, swapping the A-phase data and C-phase data of the corresponding power supply branch.

[0013] In one embodiment, the three-phase identification method for low-voltage distribution substations further includes: when the determination result is that the three-phase sequence of the corresponding power supply branch is a positive phase sequence, injecting a topological characteristic current from phase B into the corresponding power supply branch through the data acquisition unit, and acquiring the topological characteristic current through the fusion terminal to obtain current data; analyzing the current data to determine whether the phase of the current data is correct.

[0014] In one embodiment, analyzing the current data and determining whether the phase of the current data is correct includes: analyzing the current data and determining whether the phase of the current data is phase B; if the determination result is that the phase of the current data is phase B, determining that the phase of the corresponding power supply branch is correct.

[0015] In one embodiment, analyzing the current data and determining whether the phase of the current data is correct further includes: if the determination result is that the phase of the current data is not phase B, determining that the phase of the corresponding power supply branch is incorrect.

[0016] In one embodiment, the three-phase identification method for the low-voltage distribution substation further includes: issuing an abnormality warning message when it is determined that the phase of the corresponding power supply branch is incorrect, prompting the phase of the corresponding current data to be corrected according to the abnormality warning message.

[0017] According to a second aspect of the present invention, a three-phase identification system for low-voltage distribution substations is provided.

[0018] In one embodiment, the low-voltage distribution substation three-phase identification system includes:

[0019] The configuration module is used to install data acquisition units for emitting topological characteristic currents on each power supply branch of the low-voltage distribution transformer area, and to install a fusion terminal at the main incoming line of the low-voltage distribution transformer area.

[0020] The voltage acquisition module is used to inject topological characteristic current from phase B of each power supply branch as a reference angle through the data acquisition unit, and to acquire voltage data of phase A and phase C of the corresponding power supply branch through the fusion terminal.

[0021] The phase sequence determination module is used to calculate the phase angles of phases A and C of the corresponding power supply branch based on the voltage data, compare the phase angles with the reference angles, and determine the three-phase sequence of the corresponding power supply branch based on the comparison results.

[0022] In one embodiment, when the phase sequence determination module compares the phase angle with the reference angle and determines the three-phase phase sequence of the corresponding power supply branch based on the comparison result, the phase angle is compared with the reference angle. If the comparison result shows that the voltage of phase A exceeds phase B by 120° and the voltage of phase C lags phase B by 120°, the three-phase phase sequence of the corresponding power supply branch is determined to be a positive phase sequence; otherwise, the three-phase phase sequence of the corresponding power supply branch is determined to be a negative phase sequence.

[0023] In one embodiment, the low-voltage distribution substation three-phase identification system further includes: a phase sequence processing module, used to swap the A-phase data and C-phase data of the corresponding power supply branch when the judgment result is that the three-phase phase sequence of the corresponding power supply branch is reversed.

[0024] In one embodiment, the low-voltage distribution substation three-phase identification system is characterized by further comprising: a current acquisition module and a phase judgment module, wherein the current acquisition module is used to inject topological characteristic current from phase B of the corresponding power supply branch through the data acquisition unit when the judgment result indicates that the three-phase phase sequence of the corresponding power supply branch is a positive phase sequence, and to acquire the topological characteristic current through the fusion terminal to obtain current data; the phase judgment module is used to analyze the current data and determine whether the phase of the current data is correct.

[0025] In one embodiment, when the phase determination module analyzes the current data to determine whether the phase of the current data is correct, it analyzes the current data to determine whether the phase of the current data is phase B; if the determination result is that the phase of the current data is phase B, it determines that the phase of the corresponding power supply branch is correct.

[0026] In one embodiment, when the phase judgment module analyzes the current data and determines whether the phase of the current data is correct, if the determination result is that the phase of the current data is not phase B, it determines that the phase of the corresponding power supply branch is incorrect.

[0027] In one embodiment, the low-voltage distribution substation three-phase identification system further includes: a phase processing module, used to issue an abnormality prompt message when it is determined that the phase of the corresponding power supply branch is incorrect, so as to prompt the phase of the corresponding current data to be corrected according to the abnormality prompt message.

[0028] According to a third aspect of the present invention, a computer device is provided.

[0029] In one embodiment, the computer device includes a memory and a processor, the memory storing a computer program, wherein the processor executes the computer program to implement the steps of the above-described method.

[0030] According to a fourth aspect of the present invention, a computer-readable storage medium is provided.

[0031] In one embodiment, a computer program is stored on the computer-readable storage medium, which, when executed by a processor, implements the steps of the above method.

[0032] The technical solutions provided by the embodiments of the present invention may include the following beneficial effects:

[0033] This invention ensures that the phase sequence and phase of each power supply branch in the entire low-voltage power supply area are consistent by using a method that keeps the phase sequence and phase of each branch consistent. When the phase sequence and phase of each branch are correct, it can ensure that the phase of the data acquisition unit of each branch read by the fusion terminal is correct, thereby accurately calculating the power consumption of each phase, providing an effective basis for adjusting the single-phase load of each branch, reducing line loss and effectively identifying electricity theft.

[0034] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Attached Figure Description

[0035] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0036] Figure 1 This is a flowchart illustrating a three-phase identification method for a low-voltage distribution substation according to an exemplary embodiment;

[0037] Figure 2This is a schematic diagram illustrating the structure of a three-phase identification system for a low-voltage distribution substation, according to an exemplary embodiment.

[0038] Figure 3 This is a schematic diagram of the structure of a computer device according to an exemplary embodiment. Detailed Implementation

[0039] The following description and accompanying drawings fully illustrate specific embodiments described herein to enable those skilled in the art to practice them. Some embodiments may include or substitute parts and features of other embodiments. The scope of the embodiments herein encompasses the entire scope of the claims and all available equivalents thereof. Throughout this document, the terms “first,” “second,” etc., are used only to distinguish one element from another without requiring or implying any actual relationship or order between the elements. Indeed, a first element can also be referred to as a second element, and vice versa. Furthermore, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a structure, apparatus, or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a structure, apparatus, or device. Without further limitation, an element defined by the phrase “comprising one…” does not exclude the presence of other identical elements in the structure, apparatus, or device that includes said element. The various embodiments described herein are presented in a progressive manner, with each embodiment focusing on its differences from other embodiments; similar or identical parts between embodiments can be referred to interchangeably.

[0040] The terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer" used in this document to indicate orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings. They are used solely for the convenience of describing the document and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. In the description herein, unless otherwise specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to mechanical or electrical connections, or internal connections between two elements; they can be direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0041] In this document, unless otherwise stated, the term "multiple" means two or more.

[0042] In this article, the character " / " indicates that the objects before and after it are in an "or" relationship. For example, A / B means: A or B.

[0043] In this article, the term "and / or" describes an association between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or A and B.

[0044] It should be understood that although the steps in the flowchart are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order constraint on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the diagram may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the sub-steps or stages of other steps.

[0045] The modules in the apparatus or system of this application can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device in hardware form, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0046] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0047] Figure 1 An embodiment of a three-phase identification method for a low-voltage distribution station area according to the present invention is shown.

[0048] In this optional embodiment, the three-phase identification method for low-voltage distribution substations includes:

[0049] Step S101: Install data acquisition units for transmitting topology characteristic current on each power supply branch of the low-voltage distribution transformer area, and install a fusion terminal at the main incoming line of the low-voltage distribution transformer area.

[0050] Step S103: Using phase B of each power supply branch as the reference angle, inject topological characteristic current from phase B of the corresponding power supply branch through the data acquisition unit, and collect voltage data of phase A and phase C of the corresponding power supply branch through the fusion terminal.

[0051] Step S105: Calculate the phase angles of phases A and C of the corresponding power supply branch based on the voltage data, compare the phase angles with the reference angles, and determine the three-phase sequence of the corresponding power supply branch based on the comparison results.

[0052] Step S107: If the determination result is that the three-phase sequence of the corresponding power supply branch is reversed, the A-phase data and C-phase data of the corresponding power supply branch are swapped; if the determination result is that the three-phase sequence of the corresponding power supply branch is positive, the topological characteristic current is injected into the corresponding power supply branch from phase B through the data acquisition unit, and the topological characteristic current is acquired through the fusion terminal to obtain current data.

[0053] Step S109: Analyze the current data to determine whether the phase of the current data is phase B; if the determination result is that the phase of the current data is phase B, determine that the phase of the corresponding power supply branch is correct; determining whether the phase of the current data is correct also includes: if the determination result is that the phase of the current data is not phase B, determine that the phase of the corresponding power supply branch is incorrect, and issue an abnormal prompt message to prompt the phase of the corresponding current data to be corrected according to the abnormal prompt message.

[0054] In one embodiment, when comparing the phase angle with the reference angle and determining the three-phase sequence of the corresponding power supply branch based on the comparison result, if the comparison result shows that the voltage of phase A exceeds phase B by 120° and the voltage of phase C lags phase B by 120°, the three-phase sequence of the corresponding power supply branch is determined to be a positive phase sequence; otherwise, the three-phase sequence of the corresponding power supply branch is determined to be a negative phase sequence.

[0055] Figure 2 An embodiment of a three-phase identification system for a low-voltage distribution area according to the present invention is shown.

[0056] In this optional embodiment, the low-voltage distribution substation three-phase identification system includes:

[0057] Configuration module 201 is used to install data acquisition units for emitting topology characteristic current on each power supply branch of the low-voltage distribution transformer area, and to install a fusion terminal at the main incoming line of the low-voltage distribution transformer area.

[0058] The voltage acquisition module 203 is used to inject topological characteristic current from phase B of each power supply branch as a reference angle through the data acquisition unit, and to acquire voltage data of phase A and phase C of the corresponding power supply branch through the fusion terminal.

[0059] The phase sequence determination module 205 is used to calculate the phase angles of phase A and phase C of the corresponding power supply branch based on the voltage data, compare the phase angles with the reference angles, and determine the three-phase sequence of the corresponding power supply branch based on the comparison results.

[0060] The phase sequence processing module 207 is used to swap the A-phase data and C-phase data of the corresponding power supply branch when the judgment result is that the three-phase phase sequence of the corresponding power supply branch is reversed.

[0061] The current acquisition module 209 is used to inject topological characteristic current from phase B of the corresponding power supply branch through the data acquisition unit when the judgment result is that the three-phase phase sequence of the corresponding power supply branch is a positive phase sequence, and to acquire the topological characteristic current through the fusion terminal to obtain current data.

[0062] The phase judgment module 211 is used to analyze the current data and determine whether the phase of the current data is phase B; if the judgment result is that the phase of the current data is phase B, the phase of the corresponding power supply branch is determined to be correct; if the judgment result is that the phase of the current data is not phase B, the phase of the corresponding power supply branch is determined to be incorrect.

[0063] The phase processing module 213 is used to issue an abnormality prompt message when it is determined that the phase of the corresponding power supply branch is incorrect, so as to prompt the phase of the corresponding current data to be corrected according to the abnormality prompt message.

[0064] In one embodiment, when the phase sequence determination module 205 compares the phase angle with the reference angle and determines the three-phase phase sequence of the corresponding power supply branch based on the comparison result, the phase angle is compared with the reference angle. If the comparison result is that the voltage of phase A exceeds phase B by 120° and the voltage of phase C lags phase B by 120°, the three-phase phase sequence of the corresponding power supply branch is determined to be a positive phase sequence; otherwise, the three-phase phase sequence of the corresponding power supply branch is determined to be a negative phase sequence.

[0065] In one embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 3 As shown, the computer device includes a processor, memory, and a network interface connected via a system bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The database stores static and dynamic information data. The network interface communicates with external terminals via a network connection. When the computer program is executed by the processor, it implements the steps in the above method embodiments.

[0066] Those skilled in the art will understand that Figure 3The structure shown is merely a block diagram of a portion of the structure related to the present invention and does not constitute a limitation on the computer device to which the present invention is applied. A specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0067] In one embodiment, a computer device is also provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above method embodiments.

[0068] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon that, when executed by a processor, implements the steps in the method embodiments described above.

[0069] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the methods described above. Any references to memory, storage, databases, or other media used in the embodiments provided by this invention can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, or optical storage, etc. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.

[0070] This invention is not limited to the structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this invention is limited only by the appended claims.

Claims

1. A three-phase identification method for a low-voltage distribution transformer area, characterized in that, include: Data acquisition units for transmitting topological characteristic currents are installed on each power supply branch of the low-voltage distribution transformer area, and a fusion terminal is installed at the main incoming line of the low-voltage distribution transformer area. Using phase B of each power supply branch as the reference angle, the data acquisition unit injects topological characteristic current from phase B into the corresponding power supply branch, and the fusion terminal collects the voltage data of phase A and phase C of the corresponding power supply branch. Based on the voltage data, the phase angles of phases A and C of the corresponding power supply branch are calculated, and the phase angles are compared with the reference angles. Based on the comparison results, the three-phase sequence of the corresponding power supply branch is determined.

2. The three-phase identification method for low-voltage distribution transformer areas according to claim 1, characterized in that, Comparing the phase angle with the reference angle, and determining the three-phase sequence of the corresponding power supply branch based on the comparison result, includes: The phase angle is compared with the reference angle. If the comparison result shows that the voltage of phase A exceeds phase B by 120° and the voltage of phase C lags phase B by 120°, the three-phase sequence of the corresponding power supply branch is determined to be a positive phase sequence; otherwise, the three-phase sequence of the corresponding power supply branch is determined to be a negative phase sequence.

3. The three-phase identification method for low-voltage distribution transformer areas according to claim 2, characterized in that, Also includes: If the judgment result indicates that the three-phase sequence of the corresponding power supply branch is reversed, the A-phase data and C-phase data of the corresponding power supply branch will be swapped.

4. The three-phase identification method for low-voltage distribution transformer areas according to claim 2, characterized in that, Also includes: If the determination result is that the three-phase sequence of the corresponding power supply branch is a positive phase sequence, the topological characteristic current is injected into the corresponding power supply branch from phase B through the data acquisition unit, and the topological characteristic current is acquired through the fusion terminal to obtain current data. The current data is analyzed to determine whether the phase of the current data is correct.

5. The three-phase identification method for low-voltage distribution transformer areas according to claim 4, characterized in that, Analyzing the current data and determining whether the phase of the current data is correct includes: The current data is analyzed to determine whether the phase of the current data is phase B; If the current data is determined to be phase B, then the phase of the corresponding power supply branch is correct.

6. The three-phase identification method for low-voltage distribution transformer areas according to claim 5, characterized in that, Analyzing the current data and determining whether the phase of the current data is correct also includes: If the determination result indicates that the phase of the current data is not phase B, then the phase of the corresponding power supply branch is determined to be incorrect.

7. The three-phase identification method for low-voltage distribution transformer areas according to claim 6, characterized in that, Also includes: If an error is detected in the phase of the corresponding power supply branch, an abnormality warning message is issued, prompting the phase of the corresponding current data to be corrected based on the abnormality warning message.

8. A three-phase identification system for a low-voltage distribution substation, characterized in that, include: The configuration module is used to install data acquisition units for emitting topological characteristic currents on each power supply branch of the low-voltage distribution transformer area, and to install a fusion terminal at the main incoming line of the low-voltage distribution transformer area. The voltage acquisition module is used to inject topological characteristic current from phase B of each power supply branch as a reference angle through the data acquisition unit, and to acquire voltage data of phase A and phase C of the corresponding power supply branch through the fusion terminal. The phase sequence determination module is used to calculate the phase angles of phases A and C of the corresponding power supply branch based on the voltage data, compare the phase angles with the reference angles, and determine the three-phase sequence of the corresponding power supply branch based on the comparison results.

9. The three-phase identification system for low-voltage distribution transformer areas according to claim 8, characterized in that, When the phase sequence determination module compares the phase angle with the reference angle and determines the three-phase phase sequence of the corresponding power supply branch based on the comparison result, it compares the phase angle with the reference angle. If the comparison result shows that the voltage of phase A exceeds phase B by 120° and the voltage of phase C lags phase B by 120°, the three-phase phase sequence of the corresponding power supply branch is determined to be a positive phase sequence; otherwise, the three-phase phase sequence of the corresponding power supply branch is determined to be a negative phase sequence.

10. The three-phase identification system for low-voltage distribution transformer areas according to claim 9, characterized in that, Also includes: The phase sequence processing module is used to swap the A-phase data and C-phase data of the corresponding power supply branch when the judgment result is that the three-phase phase sequence of the corresponding power supply branch is reversed.

11. The three-phase identification system for low-voltage distribution transformer areas according to claim 9, characterized in that, Also includes: The current acquisition module and the phase determination module, among which, The current acquisition module is used to inject topological characteristic current from phase B of the corresponding power supply branch through the data acquisition unit when the judgment result is that the three-phase phase sequence of the corresponding power supply branch is a positive phase sequence, and to acquire the topological characteristic current through the fusion terminal to obtain current data. The phase determination module is used to analyze the current data and determine whether the phase of the current data is correct.

12. The three-phase identification system for low-voltage distribution substations according to claim 11, characterized in that, When the phase judgment module analyzes the current data to determine whether the phase of the current data is correct, it analyzes the current data to determine whether the phase of the current data is phase B; if the determination result is that the phase of the current data is phase B, it determines that the phase of the corresponding power supply branch is correct.

13. The three-phase identification system for low-voltage distribution transformer areas according to claim 12, characterized in that, When the phase judgment module analyzes the current data and determines whether the phase of the current data is correct, if the determination result is that the phase of the current data is not phase B, it determines that the phase of the corresponding power supply branch is incorrect.

14. The three-phase identification system for low-voltage distribution substations according to claim 13, characterized in that, Also includes: The phase processing module is used to issue an abnormality prompt when it determines that the phase of the corresponding power supply branch is incorrect, so as to prompt the phase of the corresponding current data to be corrected according to the abnormality prompt.

15. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 7.

16. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method of any one of claims 1 to 7.

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